益生菌对高血压影响的研究进展

肠道菌群在代谢综合征、心血管疾病和结直肠癌等疾病中的研究已经成为焦点,但是肠道微生物与这些疾 病的因果关系以及相应的致病机制尚不清楚。通过分析肠道菌群结构、组成以及代谢活动的变化对高血压的影响, 能够揭示肠道以及肠道微生物的活动与高血压之间的相关性。益生菌是对机体健康产生有益作用的活的微生物,可 以调节肠道微生态的平衡以及肠道微生物的代谢活动,从而对高血压的调节产生影响,进而为以肠道微生物为靶点 干预治疗高血压疾病提供理论参考,同时也为疾病的干预治疗提供新的途径和方法。     

提取紫薯淀粉的副产物对SHR 血压的影响

以紫薯为原料,12 周龄雄性原发性高血压大鼠(SHR)和Wistar 大鼠为受试动物,研究紫薯全粉、滤渣、淀粉、水溶性提取物的降血压作用。上述分别以低、中、高3 个剂量(0.1、1、5g/ kg bw)灌胃SHR 大鼠和Wistar大鼠,观察对大鼠血压的影响。结果表明：在所选定的灌胃剂量范围内紫薯各成分对正常大鼠(Wistar 大鼠)血压无影响。除淀粉外,其他各成分对SHR 大鼠的血压均具有显著降低的作用,其中以水溶性提取物作用最为明显,灌胃后,低剂量组在1h 时达到最低值,下降了 20.83mmHg,中剂量组在2h 时达到最低值,下降了23.50mmHg,高剂量组在4h 时达到最低值,下降了24.48mmHg,然后血压开始慢慢回升,在8h 时基本恢复到灌胃前的水平。提取紫薯淀粉后的副产物均有明显降血压作用。     

蓝莓果汁及不同纯度蓝莓花色苷对原发性高血压大鼠血压的影响

以蓝莓果汁及不同纯度的蓝莓花色苷提取物为原料灌胃12 周龄原发性高血压大鼠（spontaneouslyhypertensive rats,SHR）和Wistar大鼠,研究花色苷提取纯化对其降压效果影响。采用蓝莓果汁（A组）（花色苷的质量分数为1.00%）及不同纯度的蓝莓花色苷提取物（花色苷的质量分数分别为8.66%（B组）、38.49%（C组）、94.42%（D组））灌胃SHR,灌胃剂量以花色苷含量计。其中,A组的灌胃剂量为94.4、472.1、944.2 mg/kg（以体质量计,下同）,B组的灌胃剂量为10.9、54.5、109.0 mg/kg,C组的灌胃剂量为2.5、12.3、24.5 mg/kg,D组的灌胃剂量为1.0、5.0、10.0 mg/kg。结果表明：同剂量（花色苷当量）的蓝莓果汁与蓝莓皮渣提取物（不同纯度蓝莓花色苷提取物）相比,其对SHR的降压效果有显著差异（P＜0.05）,而同剂量不同纯度的蓝莓皮渣提取物对SHR的降压效果无显著差异（P＞0.05）。其中,高剂量果汁（A组）和不同纯度蓝莓花色苷提取物（B、C、D组）灌胃SHR,灌胃后4或5 h其收缩压分别降低了38.45、32.57、33.09、33.41 mmHg。因此,蓝莓对高血压改善作用的功能成分是花色苷;蓝莓果汁的其他成分对花色苷的降血压功能有增强作用。     

Antihypertensive Properties of a Pea Protein Hydrolysate during Short‐ and Long‐Term Oral Administration to Spontaneously Hypertensive Rats

This study investigated short‐term (24 h) and long‐term (5 wk) systolic blood pressure (SBP)‐lowering effects in spontaneously hypertensive rats (SHR) of a 5 kDa membrane pea protein hydrolysate permeate (PPH‐5) produced through thermoase hydrolysis of pea protein isolate (PPI). Amino acid analysis showed that the PPH‐5 had lower contents of sulfur‐containing amino acids than the PPI. Size‐exclusion chromatography indicated mainly low molecular weight (<10 kDa) peptides in PPH‐5 but not in the PPI. The PPH‐5 had renin and angiotensin converting enzyme inhibition IC₅₀ values of 0.57 and 0.10 mg/mL (P < 0.05), respectively, and consisted mainly of peptides with 2 to 6 amino acids. Mass spectrometry analysis revealed mainly hydrophilic tetrapeptide sequences. After a single oral administration (100 mg/kg body weight) to SHR, the unheated PPI showed weakest (P < 0.05) SBP‐lowering effect with a –4 mm Hg maximum when compared to –25 mm Hg for heat‐treated PPI and –36 mm Hg for PPH‐5. Incorporation of the PPH‐5 as 0.5% or 1% (w/w) casein substitute in the SHR diet produced maximum SBP reductions of –22 or –26 mm Hg (P < 0.05), respectively after 3 wk. In comparison, the unhydrolyzed PPI produced a maximum SBP reduction of –17 mm Hg also after 3 wk. Potency of the pea products decreased in the 4th and 5th wk, though SBP values of the treated rats were still lower than the untreated control. We conclude that the antihypertensive potency of PPH‐5 may have been due to the presence of easily absorbed hydrophilic peptides.     

不同摄入量小米对小鼠肠道菌群和短链脂肪酸的影响

摄入一定量杂粮可降低一些慢性代谢疾病的发病率,但目前杂粮摄入量没有统一的标准,尚不清楚杂粮摄入过多是否会对健康产生不良影响。以小米添加量为20%、40%、60%、80%的饲料喂养3周龄C57BL/6J小鼠,持续12周,采用自动血生化分析仪、16S rRNA高通量基因测序、气相色谱-质谱联用仪分析了不同摄入量小米对小鼠血脂水平、肠道菌群和粪便短链脂肪酸的影响。结果发现,80%摄入量的小米显著增加了小鼠血清的总胆固醇、高密度脂蛋白胆固醇和低密度脂蛋白胆固醇的水平,同时增加了肠道丙酸、丁酸、异丁酸和戊酸的含量。肠道菌群分析结果表明,所有小米干预组的拟杆菌门(Bacteroidota)、Muribaculaceae的丰度上升,厚壁菌门(Firmicutes)、放线菌门(Actinobacteriota)、乳杆菌科(Lactobacillaceae)、双歧杆菌属 (Bifidobacterium)的丰度下降。摄入不同添加量小米的小鼠肠道菌群组成具有较大差异,其中20%小米摄入量组的小鼠菌群中显著富集了另枝菌属(Alistipes)、副拟杆菌属(Parabacteroides)、肠杆菌属(Enterorhabdus),而80%摄入量小米显著降低了小鼠菌群中的粪杆菌属(Faecalibaculum)、布劳特氏菌属(Blautia)和罗氏菌属(Roseburia)的丰度。研究结果表明,20%摄入量的小米就能有效调节小鼠肠道菌群,而过高摄入量(80%)的小米使小鼠血脂水平升高,降低了肠道菌群的多样性和均匀度以及有益菌的丰度,所以要理性看待杂粮的营养价值,避免过量摄入。     

含血管紧张素转化酶抑制肽的酪蛋白水解物与紫薯提取物联用对原发性高血压大鼠血压的影响

以富含血管紧张素转化酶（angiotensin converting enzyme,ACE）抑制肽的酪蛋白水解物和富含花青素的紫薯提取物为原料,灌胃12 周龄雄性原发性高血压大鼠（spontaneously hypertensive rats,SHR）和正常雄性Wistar大鼠,研究富含ACE抑制肽的酪蛋白水解物和紫薯提取物对SHR血压的影响。用不同剂量的酪蛋白水解物（10、20、30、40 mg/kg,以体质量计,下同）和紫薯提取物（5.4、10.8、21.6、32.4 mg/kg,花青素含量为9.25%）分别灌胃SHR和Wistar大鼠。然后选用酪蛋白水解物的2 个剂量组分别与紫薯提取物的3 个剂量组联合灌胃SHR。用智能无创血压计测量SHR血压变化。结果表明：富含ACE抑制肽的酪蛋白水解物和富含花青素的紫薯提取物,在实验灌胃剂量范围内均具有较好的降压效果,而且两者联用进行单次灌胃后降压效果显著提高（P＜0.05）。其中酪蛋白水解物（10 mg/kg）分别与紫薯提取物3 个剂量（5.4、10.8、21.6 mg/kg）联合灌胃SHR后4 h或者5 h,血压分别降低了（24.67±4.46）、（28.47±3.96）、（41.51±4.89） mmHg。用酪蛋白水解物（20 mg/kg）分别与紫薯提取物的3 个剂量（5.4、10.8、21.6 mg/kg）联合灌胃SHR后5 h或者6 h,SHR血压分别降低了（38.03±3.46）、（43.92±2.92）、（47.20±4.31） mmHg。两者联用灌胃后对Wistar正常大鼠的血压无影响。另外,酪蛋白水解物2 个剂量（10、20 mg/kg）和紫薯提取物（10.8 mg/kg）分别联合使用,间隔4 h灌胃1 次,每天灌胃2 次,SHR大鼠血压较灌胃前分别降低了（28.20±3.02）、（43.54±2.55） mmHg,而且能较长时间维持在较低血压水平。因此,富含ACE抑制肽的酪蛋白水解物和富含花青素的紫薯提取物联合食用对SHR的降压具有显著效果。     

Effectiveness of probiotics,prebiotics, and prebiotic‐like components in common functional foods

The bioactive ingredients in commonly consumed foods include, but are not limited to, prebiotics, prebiotic‐like components, probiotics, and postbiotics. The bioactive ingredients in functional foods have also been associated with beneficial effects on human health. For example, they aid in shaping of gut microflora and promotion of immunity. These functional components also contribute in preventing serious diseases such as cardiovascular malfunction and tumorigenesis. However, the specific mechanisms of these positive influences on human health are still under investigation. In this review, we aim to emphasize the major contents of probiotics, prebiotics, and prebiotic‐like components commonly found in consumable functional foods, and we present an overview of direct and indirect benefits they provide on human health. The major contributors are certain families of metabolites, specifically short‐chain fatty acids and polyunsaturated fatty acids produced by probiotics, and prebiotics, or prebiotic‐like components such as flavonoids, polyphenols, and vitamins that are found in functional foods. These functional ingredients in foods influence the gut microbiota by stimulating the growth of beneficial microbes and the production of beneficial metabolites that, in turn, have direct benefits to the host, while also providing protection from pathogens and maintaining a balanced gut ecosystem. The complex interactions that arise among functional food ingredients, human physiology, the gut microbiota, and their respective metabolic pathways have been found to minimize several factors that contribute to the incidence of chronic disease, such as inflammation oxidative stress.