Aged garlic extract ameliorates the oxidative stress,histomorphological, and ultrastructural changes of cisplatin‐induced nephrotoxicity in adult male rats

Aim: Aged garlic extract (AGE) is a natural dietary substance having different antioxidant free‐radical‐scavenger compounds that ameliorates the toxicity of the oxidative stress. This study aimed to investigate the effect of AGE on cisplatin (CP)‐induced nephrotoxicity in rats. Materials and Methods: Twenty‐four, adult male Wistar albino rats were randomly divided into four groups namely control, AGE‐treated (a single oral dose of 250 mg/kg/day for 21 days), CP‐treated (a single intraperitoneal dose of 7.5 mg/kg on Day 16), and AGE + CP‐treated (AGE at a dose of 250 mg/kg/once daily for 21 days and a single dose of CP of 7.5 mg/kg intraperitoneally on Day 16). Body weight and absolute and relative kidney weights of each rat were calculated. Serum creatinine, uric acid, and urea levels were determined. Level of malondialdehyde and reduced glutathione and activity of superoxide dismutase and catalase of renal tissues were measured. Renal specimens from each rat were prepared for both light and electron microscopic examinations. Results: Interstitial cell infiltration, hemorrhage, glomerular atrophy, necrosis, and tubular degeneration were observed after CP treatment. Superoxide dismutase and catalase activities and glutathione level were significantly decreased and malondialdehyde level was significantly increased in CP‐treated rats compared with AGE + CP‐treated animals. A remarkable improvement in the histopathological and ultrastructural changes induced by CP in renal tissues was observed in AGE + CP‐treated rats. Conclusion: AGE exhibited antioxidant effect that could ameliorate the nephrotoxic effects of CP. Microsc. Res. Tech. 78:452–461, 2015. © 2015 Wiley Periodicals, Inc.     

Role of resistance physical exercise in preventing testicular damage caused by chronic ethanol consumption in UChB rats

Ethanol consumption is associated with spermatogenesis damage and testosterone level alterations. Alcohol remains the most commonly used substance among athletes and sports enthusiasts. This study evaluated whether resistance physical exercise can reduce the testicular damage caused by ethanol exposure. A total of 36 ethanol drinking (UChB) rats were divided into four groups: C (control rats), ETOH (ethanol consumption), ETOH + T (ethanol consumption + physical training), and T (group physical training). The physical training component of the T and ETOH + T groups was based on a resistance training model consisting of four sets of 10 jumps, with an increasing overload of 50–70% of the body weight attached to the chest three times per week. Rats in the ETOH and ETOH +T groups received 10% ethanol. At postnatal day 90, the rats were sacrificed. Blood sample was collected for hormonal analysis, and the testicles were weighed and processed for histopathological, morphometric, and immunohistochemical analyses. The ETOH group showed an increase in testosterone levels. The immunohistochemical of androgen receptor and the absolute weight of the testes were higher in the ETOH and ETOH + T groups, while the ETOH animals showed a decreased weight gain index. The number of abnormal seminiferous tubules increased in the ETOH and T groups compared to those in the control group (C); however, the association with treatment (ETOH + T group) prevented this effect and decreased caspase‐3 production. In conclusion, these findings show that the combination of ethanol consumption and resistance physical exercise can prevent testicular damage in adult UChB rats.     

Ultrastructure of male reproductive system of Eurydema ventrale Kolenati 1846 (Heteroptera: Pentatomidae)

The male reproductive system of Eurydema ventrale Kolenati 1846 is studied morphologically and histologically by using light, scanning and transmission electron microscopes. The reproductive system of the male E.ventrale consists of a pair of testis, a pair of vas deferens, a pair of seminal vesicles, accessory glands, a bulbus ejaculatorius, a pair of ectodermal sacs, and a ductus ejaculatorius. The testicular follicles have three different development zones (growth zone, maturation zone, and differentiation zone). The testes are connected to the seminal vesicles by the vas deferens that is a specialized in sperm storage. Sperm have an elongated head and a tail (flagellum) with an axonema and two mitochondrial derivatives. Vas deferens and seminal vesicles are fine, long, and cylindrical. The seminal vesicle is connected with bulbus ejaculatorius, which is balloon shaped and surrounded with accessory glands. The bulbus ejaculatorius is continuous with ductus ejaculatorius which is connected to the aedeagus. Microsc. Res. Tech. 78:643–653, 2015. © 2015 Wiley Periodicals, Inc.     

The osteogenic effects of swimming on bone mass,strength, and microarchitecture in rats with unloading‐induced bone loss

The effect of nonweight‐bearing exercise on osteoporotic bones remains controversial and inconclusive. The purpose of this study was to evaluate the effects of swimming on osteoporotic tibias of rats submitted to hindlimb suspension. Initially, 20 Wistar rats were used to confirm a significant bone loss following 21 days of unloading. Thirty rats were then divided into 3 groups and followed during 51 days: CON (nonsuspended rats), S + WB (suspended rats for 21 days and then released for regular weight‐bearing) and, S + Swim (suspended rats for 21 days and then released from suspension and submitted to swimming exercise). We observed that swimming exercise was effective at fully recovering the bone deterioration caused by suspension, with significant increments in BMD, bone strength and bone volume. On the other hand, regular weight‐bearing failed at fully restoring the bone loss induced by unloading. These results indicate that swimming exercise may be a potential tool to improve bone density, strength, and trabecular volume in tibias with bone loss induced by mechanical unloading in suspended rats. We conclude that this modality of activity could be beneficial in improving bone mass, strength, and architecture in osteoporotic individuals induced by disuse, such as bed rest or those exposed to microgravity, who may not be able to perform weight‐bearing exercises. Microsc. Res. Tech. 78:784–791, 2015. © 2015 Wiley Periodicals, Inc.     

Improved Substrate Protection and Self-Healing of Boundary Lubrication Film Consisting of Polydimethylsiloxane with Cationic Side Groups

The substrate protection and self-healing capability of a cationic polymer lubricant (CPL) on a silicon oxide surface were tested with a pin-on-disc tribometer and atomic force microscopy (AFM). CPL was made of low molecular weight polydimethylsiloxane (PDMS) containing covalently attached quaternary ammonium cations and iodide counter-anions. CPL was spin-coated on the silicon oxide surface to form a 3–4 nm thick bound-and-mobile lubricant layer. The CPL film capable of binding to the SiO₂ surface through ionic interactions is superior in substrate protection than the neutral PDMS film which cannot form the bound layer. The mobile component in the CPL film readily flows into the lubricant-depleted sliding contact region from the surrounding film. The self-healing capability of CPL via lateral flow is slightly enhanced in humid environments due to water uptake in the film. The 3–4 nm thick CPL film on silicon oxide takes 30–40 s to flow into a ~50 μm wide track, which corresponds to an apparent spreading rate of 2–3 × 10⁻¹¹ m²/s.     

Organization and seasonal quantification of the intertubular compartment in the bat Molossus molossus (Pallas, 1776) testis

Environmental factors can influence the reproductive rates in bats, and since morphometric information of bats testis is scarce, we aimed to compare the organization and quantification of the intertubular components in the testes of the bat Molossus molossus, collected in different seasons. Testicular histological sections were evaluated using light and electron microscopy. The intertubular compartment occupied an average 10% of the testes, being predominately constituted of Leydig cells (LC). The percentages of the testes occupied by the intertubular compartment and by LC were significantly higher in summer, while the other intertubular components did not vary significantly among the seasons. As suspected under light microscopy, the ultrastructural analysis confirmed the existence of multinucleated LC during winter. The increase in the nuclear percentage of LC in winter seems to have caused the decrease of the cytoplasmatic measurements in that season, as well as in the volume of LC. The highest cytoplasmatic values and volume of LC registered in the spring, summer, and fall can be related to greater activity of this cell in these seasons. The higher investment in intertubular tissue and in LC observed in summer, compared to winter; suggest an increase in the steroidogenic capacity of this bat during summer. The analyses correlating testicular morphometry and abiotic environmental factors in this study confirm the influence of climatic factors on the reproduction of M. molossus. Microsc. Res. Tech., 2013. © 2012 Wiley Periodicals, Inc.     

Morphological and histological structure of the male reproductive system of the water strider Gerris lacustris (Linnaeus 1758) (Gerridae,Heteroptera)

This work presents the male reproductive system morphology and histology of the water strider Gerris lacustris (Linnaeus 1758) (Gerridae, Heteroptera) using light microscopy and scanning electron microscopy. The male reproductive system of G. lacustris comprise of a pair of testes, two vasa deferentia, two seminal vesicles, an ejaculatory duct. There is no bulbus ejaculatorius and the long vas deferantia uniting to form a simple ductus ejaculatorius which is connected to the aedeagus. The testes are white colored and this cylindiric‐shaped structure lies along genital abdominal segment. The testicular follicles have three different development zones (growth zone, maturation zone, differentiation zone). Each testis has two follicles, which are not lined by a common peritoneal sheath and involving many cysts arranged in a progressive order of maturation from the distal to the proximal region; spermiogenesis occurs in mature males, finishing with the organization of sperm bundles. The testes are connected to the seminal vesicles, specialized sperm storage places, by the vas deferentia.     

Cytopathological and ultrastructural changes in the male reproductive organs of freshwater crab Paratelphusa jacquemontii (Rathbun) exposed to nurocombi

Accumulation of pollutants in the aquatic system has a high impact on the reproductive physiology of crustaceans. The objective of the present study was to assess the possible histopathological effects of combined chlorpyrifos and cypermethrin (nurocombi) exposure on reproductive tissue in male freshwater crab Paratelphusa jacquemontii using light and electron microscopy. The testis of experimental crabs showed disorganization of testicular lobules, increased inters cellular space, necrosis, and cellular damage in both germinal cells and Sertoli cells. The treated vas deferens exhibited epithelial degeneration, misshaped spermatophores, decline in the number of spermatophores, and dehiscence of spermatophore wall. These clinical manifestations expressed in crabs following the exposure of nurocombi significantly reduce the testicular activity and substantially inhibits the seminal secretions, which ultimately lead to impairment of reproduction.     

Estimation error of Leydig cell numbers in atrophied rat testes due to the assumption of spherical nuclei

In this study, Leydig cell numbers in control and atrophied testes (induced via subcutaneous implants of testosterone plus 17β estradiol for 16 weeks; TE-implanted) of rats, estimated via the fractionator method (independent of any assumptions) were compared to those estimated via the disector (unbiased, but dependent on shrinkage) and Floderus (assumes spherical particles, dependent on shrinkage) methods. Estimates of Leydig cell numbers in control rats produced by all three stereological methods were similar. In rats with atrophied testes, both the fractionator and the disector methods produced significantly lower (P < 0.01; 47% and 41 % with fractionator and disector, respectively) Leydig cell number estimates per testis than in the controls. By contrast, the estimates of Leydig cell number in atrophied testes derived via the Floderus equation were not significantly different from those of controls, but larger than those obtained via the fractionator and the disector methods. These results suggested that the assumptions of the Floderus method were violated in the atrophied rat testes. Why was the Floderus method of estimating Leydig cell number applicable to control rats but not to the TE-implanted rats? In an attempt to answer this question the diameter measurement together with its correction factor used in the Floderus equation (i.e. D + t ? 2H) was also derived from the data collected for the disector method. The values for D + t ? 2H used in the Floderus method and also calculated via the disector method were found to be identical in controls, but for the TE-implanted rats a 32% lower value was obtained with the Floderus equation when compared to the disector. These findings suggested that this estimation error caused an overestimation of Leydig cell numbers in the TE-implanted rat testes.     

Fluorescence microscopy study on the cytoskeletal displacements during sperm differentiation in the bush‐cricket Tylopsis liliifolia (Fabricius) (Orthoptera: Tettigoniidae)

A study by fluorescence microscopy has been carried out on male gametes from testicular follicles, seminal vesicles, spermatophores, and seminal receptacles of the bush‐cricket Tylopsis liliifolia, focusing the attention on localization and movements of F‐actin and α‐tubulin during sperm differentiation, since data in this respect are lacking in the Orthoptera. F‐actin and α‐tubulin positivity was detected in the testicular follicles, in particular at the bridges connecting spermatids of a same clone and around their nucleus, during the first differentiation stages. During the following differentiation stages in the testes, F‐actin was found at one of the spermatid poles and then, during nucleus elongation, at the whole acrosomal region. A peculiar F‐actin‐positivity was found at the flagellum, more markedly immediately posterior to the nucleus, at the basal body region of the gametes from the testicular follicles and from the other examined districts. Other interesting data from our investigations concerns the α‐tubulin displacements during the differentiation stages of the spermatid and a constant absence of α‐tubulin‐positivity where the centrioles are located. No positivity was also found for both α‐tubulin and nuclear markers at the anterior region of the gamete, where the acrosomal wings are localized. Our results, compared with what is so far known in literature for the insects, lead us to assert that microfilaments and microtubules undergo gradual displacements, markedly in the testicular follicles, during the morphogenesis of the male gamete of T. liliifolia aimed to its organization and motility and probably also to its interaction with the female gamete. Microsc. Res. Tech. 79:81–88, 2016. © 2015 Wiley Periodicals, Inc.     

Alcohol extract of Bauhinia forficata link reduces lipid peroxidation in the testis and epididymis of adult Wistar rats

Bauhinia forficata is a medicinal plant that has flavonoid components with hypoglycemic, antioxidant, hepatoprotective, antibacterial, antiviral and anti‐inflammatory action. Aim of this study is to evaluate the action of B. forficata alcoholic extract in the male genital system of adult male Wistar rats. For that, 20 adult male Wistar rats were distributed into two experimental groups: the B. forficata group, receiving B. forficata alcoholic extract (0.1 ml/10 g body weight/day) on alternate days, and the control group, receiving just the vehicle for 30 days straight both via gavage. On the 31st day, the animals were euthanized, and the testis and epididymis were collected for histopathological, biochemical, morphometric, and sperm count analysis. Mass spectrometry identified new compounds in the extract: trans‐caffeic acid, liquiritigenin, gallocatechin, and 2,4,6‐trihydroxyphenanthren‐2‐glycoside. Biochemical analysis showed higher total cholesterol levels in the testis and lower malondialdehyde levels in the testis and epididymis, in the B. forficata group. The mast cell count showed a reduction in degranulated mast cells in the caput region of the epididymis, in the B. forficata group. The luminal compartment of the caput and the epithelial of the epididymis cauda were reduced, whereas the stromal region of the epididymis caput was increased in the B. forficata group, compared with the control group. The testicular tissue was less impaired, considering that all the histological analyses were similar to the control. We believe that B. forficata alcoholic extract in the male genital system showed antioxidant action, especially in the epididymal tissue.     

Involvement of the adrenal glands and testis in gap junction formation via testosterone within the male rat anterior pituitary gland

We investigated the influence of testicular and adrenal androgens on the presence of gap junctions between folliculo‐stellate cells in the anterior pituitary glands of 60‐day‐old Wistar‐Imamichi strain male rats. The animals were separated into six groups: Group A served as the controls and had free access to a normal diet and water, Group B was given a normal diet and 0.9% NaCl for their drinking water as the controls of adrenalectomized groups, Group C was castrated, Group D was adrenalectomized, Group E was both castrated and adrenalectomized, and Group F was also both castrated and adrenalectomized. In addition, the animals of Group F were administered a dose of testosterone that is known to produce high physiological levels of the hormones in plasma. Five rats from each group were sacrificed 1, 2, 3, 4, 5, 6, and 7 days after their respective operation, and the anterior pituitary glands were removed and prepared for observation by transmission electron microscopy. We quantified the number of follicles and gap junctions and calculated the rate of occurrence as the ratio of the number of gap junctions existing between folliculo‐stellate cells per intersected follicle profile. Simultaneous removal of adrenal glands with castration resulted in a significantly decrease in the number of gap junctions, whereas the administration of testosterone to these rats compensated for this change. These observations indicate that the preservation of gap junctions between folliculo‐stellate cells is mainly dependent on androgens from both the testes and adrenal glands in adult male rats. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.     

新型微小型平板CPL蒸发器流动与传热分析

提出一种新型微小型平板毛细抽吸两相流体回路(Capillary pumped loop,CPL)的蒸发器结构,使其能够适应高热流密度散热的要求。分析蒸发器由于微型化后侧壁导热对系统传热能力的影响。建立新型蒸发器毛细多孔芯内的传热传质数学模型和液体补偿腔的流动与传热模型以及蒸汽槽道和金属外壁区域的导热模型,并用SIMPLE算法对蒸发器进行整场耦合求解。数值结果表明,工质蒸发发生在多孔芯上表面以及侧壁附近,采用热导率较大的铝外壁时,蒸发器加热表面的温度水平较低且温度均匀性较好,但侧壁导热的影响导致CPL的传热能力不高。外壁采用热导率较小的不锈钢可以明显提高CPL的传热极限能力,但同时却较大地增加了加热表面的温度水平以及不均匀性。采用组合结构的蒸发器一方面可以提高系统的传热能力,同时降低了加热表面的温度水平和温度梯度。     

High-pressure freezing causes structural alterations in phospholipid model membranes

The influence of high-pressure freezing (HPF) on the lipid arrangement in phospholipid model membranes has been investigated. Liposomes consisting of pure dipalmitoylphosphatidylcholine (DPPC) and of DPPC mixed with a branched-chain phosphocholine (1,2-di(4-dodecyl-palmitoyl)-sn-glycero-3-phosphocholine) have been analysed by freeze-fracture electron microscopy. The liposomes were frozen either by plunging into liquid propane or by HPF. The characteristic macroripple-phase of the two-component liposome system is drastically changed in its morphology when frozen under high-pressure conditions. The influence of ethanol which acts as pressure transfer medium was ruled out by control experiments. In contrast, no high-pressure alterations of the pure DPPC bilayer membrane have been observed. We assume that the modification of the binary system is due to a pressure-induced relaxation of a stressed and unstable lipid molecule packing configuration. HPF was performed with a newly designed sample holder for using sandwiched copper platelets with the high-pressure freezing machine Balzers HPM010. The sandwich construction turned out to be superior to the original holder system with regard to freeze-fracturing of fluid samples. By inserting a spacer between the supports samples with a thickness of 20–100 μm can be high-pressure frozen. The sandwich holder is provided with a thermocouple to monitor cooling rates and allows exact sample temperature control. Despite a two-fold mass reduction compared to the original holder no HPF cooling rate improvement has been achieved (4000 °C s⁻¹). We conclude that the cooling process in high-pressure freezing is determined mainly by cryogen velocity.     

The histomorphological structure of the male reproductive system of maize leaf weevil Tanymecus dilaticollis Gyllenhal, 1834 (Coleoptera: Curculionidae)

The histomorphology of the reproductive system and the germ cells has been useful to establish phylogenetic relationships in many insects. However, these elements remain little known in the Curculionidae. In this study, histomorphological structure of the male reproductive system of Tanymecus dilaticollis, which is economically important, is described, illustrated using stereomicroscopy, light microscopy, and scanning electron microscopy techniques, and discussed in relation to other Coleoptera species. Results showed that distinctive features of the male reproductive system of T. dilaticollis consist of a pair of yellowish testes, a pair of seminal vesicles, a pair of vasa deferentia, an ejaculatory duct, accessory glands, prostate glands, and aedeagus. Each testis is subdivided into two testicular follicles, enclosed by a peritoneal sheath. Each follicle of the mature testes is full sperm cysts with germ cells at various stages development of spermatogenesis. The testes have four types of germ cells (spermatogonia, spermatocytes, spermatids, and spermatozoa). They are occupied by the growth zone containing spermatogonia and spermatocytes, the maturation zone containing spermatids, while differentiation zone containing spermatozoa. There is a seminal vesicle at the center of each testis. Most mature sperms are stored in the seminal vesicle. Each testis is attached to the vas deferens by a stalk‐like seminal vesicle. In the distal part, vasa deferentia fuse with the ejaculatory duct. It is linked to the aedeagus. The provided results will contribute to the understanding of the reproductive cell biology of Curculionidae.     

Elemental sulfur upregulated testicular testosterone biosynthesis by associating with altered gut microbiota in mice

Elemental sulfur has been used as a traditional Chinese medicine to treat the late-onset hypogonadism and impotence without a clarified mechanism for many hundreds of years. In the present study, mice were received sulfur or distilled water for 35 days by daily intragastric gavage at a dose of 250 mg/kg body weight. Then, the serum testosterone level and genes associated with testicular testosterone biosynthesis (TTB) were detected. The gut microbiota was also analyzed by 16S rRNA gene sequencing. Serum testosterone level was significantly increased by 291.1% in sulfur-treated mice. The H₂S levels in serum and feces were significantly increased. The expression of genes associated with TTB including StAR, p450c17, 3β-HSD, and P450scc in testes were significantly upregulated by Sulfur and NaHS, suggesting that sulfur promotes TTB depending on H₂S. In addition, sulfur increased the diversity of gut microbiota and the abundance of several bacteria associated with sulfur metabolism, including genus Prevotella, which might be positively associated with serum level of testosterone in boys. Five pathways including bile secretion, carotenoid biosynthesis, lipid biosynthesis proteins, propanoate metabolism, and biosynthesis of type II polyketide products, were identified to associate with sulfur. Together, our results suggested that sulfur upregulated testicular testosterone biosynthesis via H₂S, which was associated with alteration of gut microbiota in mice. Our study highlights a mechanism for the treatment of late-onset hypogonadism and impotence by sulfur.     

Dose–response and histopathological study,with special attention to the hypophysis,of the differential effects of domoic acid on rats and mice

The effects of the neurotoxin domoic acid (DA) in the central nervous system of rodents (essentially rats and mice) after intraperitoneal administration have been profusely studied in the past. These observations have shown that the toxin induces similar symptoms and pathology in both species, but the lethality varies greatly. This article addresses the common and specific histopathological effects in rats and mice and the difference in sensitivity of these species to DA. Various sublethal and lethal doses were employed in mice (from 3 mg/kg to 8 mg/kg) to observe their neurotoxicity by using different histological techniques, and these results were compared with the pathological effects after the administration of LD50 in rats (2.5 mg/kg). Additionally we also detected the presence of this toxin in various tissues by means of immunohistochemistry. Our results showed that rats are more vulnerable than mice to the neurotoxic effects of DA after intraperitoneal inoculation: lethality was extremely high in rats and the toxin produced hippocampal damage in rats surviving the intoxication, while lesions were not observed in DA‐inoculated mice. As for similarities between rats and mice, both displayed similar clinical signs and in both the toxin was detected in the hypophysis by immunohistochemistry, a brain region not reported to date as target of the toxin. Microsc. Res. Tech. 78:396–403, 2015. © 2015 Wiley Periodicals, Inc.     

Effect of treatment with simvastatin on bone microarchitecture of the femoral head in an osteoporosis animal model

The objective of this study was to evaluate the microarchitecture and trabecular bone strength at the distal region of the femur, and its biomechanical properties with simvastatin administration with two different doses in ovariectomized (OVX) rats. Ninety rats were divided into six groups to evaluate treatment with the simvastatin drug (n = 15): SH (Sham surgery), SH‐5 (5 mg simvastatin), SH‐20 (20 mg simvastatin), OVX, OVX‐5, and OVX‐20. Euthanasia was performed at three different times, five animals per period: 7, 14, and 28 days. The effectiveness of the treatments was evaluated by mechanical testing and histomorphometric analysis of the femurs. The results of analysis by the linear model of mixed effects showed 20 mg of simvastatin results in increased trabecular bone after 14 days (P = 0.039) of ingestion in ovariectomized animals. However, ingestion of 5 mg of simvastatin is able to sensitize the trabecular bone only at 28 days (P = 0.005) of ingestion. In the mechanical tests stiffness improves within 28 days (P = 0.003). Regarding maximum strength, no statistical differences were observed. According to these results, it can be concluded that for a decrease in oral intake, longer treatment times are required. Microsc. Res. Tech. 79:684–690, 2016. © 2016 Wiley Periodicals, Inc.     

Astaxanthin delayed the pathogenesis of diabetic nephropathy in type 1 diabetic rats

This study was designed to investigate the protective effects of Astaxanthin (AST) in rats with diabetes mellitus (DM) induced by streptozotocin. SD rats were divided into control group (n = 5, only received normal saline), DM group (n = 8) and AST + DM group (n = 8; AST: 50 mg/kg/day). DM rats were induced by intraperitoneal injection of streptozocin (STZ, 65 mg/kg). Blood glucose level and body weight were determined at weeks 0, 2, 4, 6 and 8, respectively. At week 8, kidney function was determined, together with expression of P53 and dynamin-related protein-1 (Drp1) by Western blot analysis and immunofluorescence. AST led to increase of body weight in rats with DM. AST + DM group showed a significant decrease in blood glucose level at week 4 compared with DM group (P < 0.05). AST improved renal function and significantly reduced expression of P53 and Drp1 in DM rats. In addition, AST can effectively reduce the blood glucose in DM rats, and delayed the pathogenesis of diabetic nephropathy. Such delay mediated by AST may be associated with the downregulation of Drp1 and P53.     

Nitric oxide regulates mitochondrial re‐modelling in interscapular brown adipose tissue: ultrastructural and morphometric‐stereologic studies

As a complex, cell‐specific process that includes both division and clear functional differentiation of mitochondria, mitochondriogenesis is regulated by numerous endocrine and autocrine factors. In the present ultrastructural study, in vivo effects of l ‐arginine‐nitric oxide (NO)‐producing pathway on mitochondriogenesis in interscapular brown adipose tissue (IBAT) were examined. For that purpose, adult Mill Hill hybrid hooded rats were receiving l ‐arginine, a substrate of NO synthases (NOSs), or N^ω‐nitro‐l ‐arginine methyl ester (l ‐NAME), an inhibitor of NOSs, as drinking liquids for 45 days. All experimental groups were divided into two sub‐groups – acclimated to room temperature and cold. IBAT mitochondria were analyzed by transmission electron microscopy and stereology. l ‐Arginine treatment acted increasing the number of mitochondrial profiles per cell profile, as well as volume fraction of mitochondria per cell volume in animals maintained at room temperature. Cold‐induced enhancement of number of mitochondrial profiles per cell profile was additionally increased in l ‐arginine‐treated rats. Ultrastructural examinations of l ‐arginine‐treated cold‐acclimated animals clearly demonstrated thermogenically active mitochondria (larger size, lamellar, more numerous and well‐ordered cristae in their profiles), which however were inactive in l ‐arginine‐receiving animals kept at room temperature (small mitochondria, tubular cristae). By contrast, l ‐NAME treatment of rats acclimated to room temperature induced mitochondrial alterations characterized by irregular shape, short disorganized cristae and megamitochondria formation. These results showed that NO is a necessary factor for mitochondrial biogenesis and that it acts intensifying this process, but NO alone is not a sufficient stimulus for in vivo induction of mitochondriogenesis in brown adipocytes.