Nostoc sphaeroids Kütz ameliorates hyperlipidemia and maintains the intestinal barrier and gut microbiota composition of high-fat diet mice

Effects of natural products on functional constipation: analysis of active ingredient and mechanism

Constipation is a prevalent clinical ailment of the gastrointestinal system, yet its pathogenesis remains ambiguous. Despite the availability of numerous treatment modalities, they are insufficient in resolving the issue for patients. This work conducted a comprehensive review of the existing literature pertaining to the utilization of natural products for the treatment of constipation, with a focus on the efficacy of natural products in treating constipation, and to provide a comprehensive summary of their underlying mechanisms of action. Upon conducting a thorough review of the extant literature, we found that natural products can effectively treat constipation as modern synthetic drugs and compounded drugs with acetylcholinesterase (AChE) effects, rich in fiber and mucus, and the effects of increasing the tension of the ileum and gastrointestinal tract muscle, mediating signaling pathways, cytokine, excitability of the smooth muscle of the gastrointestinal tract, and regulating the homeostasis of intestinal flora. However, there is a wide variety of natural products, and there are still relatively few studies; the composition of natural products is complex, and the mechanism of action of natural products cannot be clarified. In the future, we need to further improve the detailed mechanism of natural products for the treatment of constipation.

Risk factors for small intestinal bacterial overgrowth in patients with acute ischaemic stroke

Introduction. The intestinal flora has become a promising new target in acute ischaemic stroke (AIS), and small intestinal bacterial overgrowth (SIBO) is a common pathological condition of the intestinal flora. Recently, the lactose hydrogen-methane breath test has emerged as a non-invasive and economical method for the detection of SIBO in AIS patients. Exploring the prevalence of SIBO and its associated risk factors will provide a clinical basis for the association between intestinal flora and AIS.Hypothesis/Gap Statement. Given that the prevalence of SIBO and its risk factors in patients with AIS remain to be studied, there is a need to investigate them.Aim. This study aimed to investigate the prevalence and risk factors of SIBO in patients with AISMethodology. Eighty patients tested for SIBO using the lactulose hydrogen-methane breath test were evaluated. Patients were divided into SIBO-positive and SIBO-negative groups according to the presence or absence of SIBO, respectively. The baseline characteristics and clinical biochemical indicators of the patients were compared between the two groups. The independent risk factors and predictive value of SIBO in AIS patients were determined using multivariate logistic regression and receiver operating characteristic (ROC) curve analyses.Results. Of the 80 consecutive patients with AIS, 23 (28.8 %) tested positive for SIBO. Triglyceride (TG) and homocysteine (Hcy) levels were identified as independent risk factors for SIBO in patients with AIS using multivariate logistic regression analysis (P<0.005). ROC curve analysis showed that the area under the curve (AUC) of TG was 0.690 (95 % CI 0.577-0.789, P=0.002). The sensitivity, specificity and optimal cut-off values were 95.7 %, 35.1 % and 1.14 mmol l^-1, respectively. The AUC of Hcy was 0.676 (95 % CI 0.562-0.776, P=0.01). The sensitivity, specificity and optimal cut-off values were 73.9 %, 59.7 % and 14.1 µmol^-1, respectively. When TG and Hcy levels were combined, the AUC increased to 0.764 (95 % CI 0.656-0.852, P<0.001). The specificity and sensitivity were 61.4 and 82.6 %, respectively. This showed that the combined detection of TG and Hcy levels had a higher predictive valueConclusion. The prevalence of SIBO in patients with AIS was 28.8 %. TG and Hcy levels are independent risk factors for SIBO in patients with AIS. Both markers had good predictive value for the occurrence of SIBO. In the future, we should actively utilize these indicators to prevent intestinal flora imbalance and the occurrence of SIBO.

Protective Mechanism of Nostoc sphaeroides Kütz. Polysaccharide on Liver Fibrosis by HFD-Induced Liver Fat Synthesis and Oxidative Stress

Nostoc sphaeroides Kütz. polysaccharide (NSKP) is one of the main components of Nostoc sphaeroides Kütz. and is often used as health food. We investigated whether NSKP interferes with the progression of liver fibrosis. Male mice were randomly divided into 4 groups: control (C), high-fat diet (M), high-fat diet + 0.4 g/kg NSKP (L), and high-fat diet + 0.8 g/kg NSKP (H). C was fed standard diet, M was fed high-fat diet, and L and H were fed high-fat diet in addition to gavage of 0.4 g/kg or 0.8 g/kg NSKP, respectively, for 22 weeks. At the end of the experiment, the serum and liver oxidative stress, fat accumulation, and fibrosis indexes were detected. The histopathology of liver was also observed. The results showed that the rice of NSKP, compared with M, improved blood lipid level, liver total cholesterol (TC), triglyceride (TG), and liver antioxidant capacity and effectively interfered with liver fibrosis related indicators. So it is interesting to note that NSKP appeared to be effective in liver injury; further experiments are necessary to clarify the exact mechanisms involved.

Effects of Nostoc sphaeroids Kütz polysaccharide on renal fibrosis in high-fat mice

In this study, we investigated the effects of Nostoc sphaeroids Kütz polysaccharide (NSKP) on renal fibrosis in high‐fat mice. ApoE^−/− male mice were randomly divided into four groups: control (Cont) group, high‐fat diet (HFD) group, HFD+0.4 g/kg BW NSKP, and HFD+0.8 g/kg BW NSKP (NSKP groups). The Cont was fed a standard diet. The HFD group was fed HFD. Every day, NSKP groups were fed HFD, as well as given 0.4 g/kg BW or 0.8 g/kg BW NSKP. After 22 weeks, the serum biochemical indices (TC, TG, LDL‐C, HDL‐C, GLU, BUN, and SCR) were measured. For the kidney, the histopathological sections were observed and analyzed, and inflammatory factors and markers of renal fibrosis were measured. For the NSKP groups, the serum TC, TG, LDL‐C, BUN, and SCR were decreased, HDL‐C significantly increased compared with the HFD group. The protein expressions of TNF‐α, IL‐1β, and TGF‐β1 were significantly downregulated. The α‐SMA in renal cortex was decreased, and the mRNA expression of Col‐I and Col‐IV in renal collagen fibers was downregulated. To sum up, NSKP reduced the blood lipid of HFD mice, downregulated the inflammation of kidney, inhibited the expression of collagen fiber, and improved the renal fibrosis caused by long‐term lipid metabolism disorder.

Nostoc sphaeroides Cyanobacteria: a review of its nutritional characteristics and processing technologies

Nostoc sphaeroides is an edible Cyanobacterium which has high nutritional value and is widely used in dietary supplements and therapeutic products. N. sphaeroides contains protein, fatty acid, minerals and vitamins. Its polysaccharides, phycobilin, phycobiliproteins and some lipids are highly bioactive. Thus, N. sphaeroides possesses anti-oxidation, anti-inflammation and cholesterol reducing functions. This paper reviews and evaluates the literature on nutritionally and functionally important compounds of N. sphaeroides. It also reviews and evaluates the processing of technologies used to process N. sphaeroides from fresh harvest to dry particulates including pretreatment, sterilization and drying, including their impact on sensorial and nutritional values. This review shows that a suitable combination of ultrasound, radio frequency and pulse spouted microwave with traditional sterilization and drying technologies greatly improves the sensorial and nutritive quality of processed N. sphaeroides and improves their shelf life; however, further research is needed to evaluate these hybrid technologies. Once suitably processed, N. sphaeroides can be used in food, cosmetics and pharmaceutical drugs as an ingredient.

Effect of Plant-Derived n-3 Polyunsaturated Fatty Acids on Blood Lipids and Gut Microbiota: A Double-Blind Randomized Controlled Trial

Background

Several cardioprotective mechanisms attributed to n-3 polyunsaturated fatty acids (PUFAs) have been widely documented. Significant interest has recently focused on the role of human gut microbiota in metabolic disorders. However, the role of plant-derived n-3 PUFAs on blood lipid profiles is controversial and the effect on gut microbiota is still unclear.

Objectives

We aimed to perform a double-blind randomized controlled trial to test the effect of plant-derived n-3 PUFAs on the blood lipids and gut microbiota of patients with marginal hyperlipidemia.

Methods

According to the inclusion and exclusion criteria, 75 participants with marginal hyperlipidemia were randomly assigned to the intervention group (supplied with n-3 PUFA-enriched plant oil) or control group (supplied with corn oil), respectively, for a 3-month treatment. Participants and assessors were blinded to the allocation. The primary outcomes of the trial were the changes in serum lipid levels. Secondary outcomes were changes in gut microbiota and metabolites. For the primary outcomes, we conducted both an intent-to-treat (ITT) analysis and a per protocol (PP) analysis. For the secondary outcomes, we only conducted the PP analysis among the participants who provided fecal sample.

Results

Fifty-one participants completed the trial. Relative to the control group, the n-3 PUFA supplementation resulted in significant reduction in total cholesterol (TC) levels (−0.43 mmol/L, 95% CI−0.84 to−0.01 mmol/L, P < 0.05). The n-3 PUFA supplementation was also associated with significantly increased relative abundance of Bacteroidetes in phylum level (P < 0.01; false discovery rate (FDR) corrected p = 0.11), and decreased the ratio between Firmicutes and Bacteroidetes (P < 0.05; FDR corrected p = 0.16). At genus level, the intervention of plant derived n-3 PUFAs resulted in a significant decrease in relative abundance of Phascolarctobacterium (P < 0.01; FDR corrected p = 0.18) and Veillonella (P < 0.01; FDR corrected p = 0.18) after the intervention.

Conclusions

Our results demonstrated that plant-derived n-3 PUFAs beneficially affected the serum levels of TC and decreased the ratio between Firmicutes and Bacteroidetes during the 12-week intervention period, which might confer advantageous consequences for lipid metabolism and intestinal health.

Egg consumption improves vascular and gut microbiota function without increasing inflammatory, metabolic, and oxidative stress markers

Egg consumption is one of the many inconsistencies in evidence linking dietary cholesterol to cardiovascular disease (CVD). In addition, the gut microbiota and its metabolite, trimethylamine-N-oxide (TMAO), have been shown to play a crucial role in the development of CVD. The fact that egg is rich in choline suggests that excessive egg consumption may increase TMAO production by altering the gut microbiota. However, the effects of egg consumption on vascular function and gut microbiota remain unclear. Here, the diet of nine young male subjects was supplemented with two boiled eggs daily for 2 weeks. Changes in vascular function, inflammation, metabolism, oxidative stress, and gut microbiota were examined. We found that egg consumption increased flow-mediated dilation and decreased brachial-ankle pulse wave velocity. Furthermore, egg consumption positively modulated the gut microbiota function but had no effects on the levels of C-reactive protein, glucose, lipid profile, malondialdehyde, superoxide dismutase, or TMAO. The current study provides evidence that egg consumption improves vascular function, which may be related to the alterations seen in the gut microbiota. Therefore, moderate egg consumption may help to improve vascular and intestinal function in individuals at low risk of developing CVD and other metabolic disorders.

Nostoc sphaeroides Kütz Polysaccharide Improved Constipation and Promoted Intestinal Motility in Rats

Natural products and medicinal foods have attracted more and more attention because of their potential prevention and inhibition effect on constipation. Nostoc sphaeroides Kütz Polysaccharide (NSKP) polysaccharide is a natural product rich in polysaccharides. This work attempted to prove the effects of aqueous extracts of NSKP on STC treatment and to determine the possible mechanisms by a loperamide-induced slow transit constipation (STC) model. The results show that, in rats of the NSKP group, compared with the model group, the colon propulsion rate was improved, the time of the first grain of black stool was shortened, and the fecal wet weight was increased remarkably. The 5-HT levels were increased, but the VIP and NO levels were reduced dramatically. The number of interstitial cells of cajal (ICC) was increased by c-kit/SCF signal pathway, and the intestines were moisturized; then, constipation was relieved. It is interesting to note that NSKP appeared to be effective on constipation, so further experiments are necessary to clarify the exact mechanisms involved.

Nostoc sphaeroids Kütz polysaccharide and powder enrich a core bacterial community on C57BL/6j mice

Gut microbiota is the collection of microbes that lives in the host. Glycan is the major factor to shape the composition of microbial community. Nostoc sphaeroids Kütz (NSK) has been used as food and medicine for thousands of years in Asian countries while the bioactivity on gut microbiota is unclear till now. Here, we used NSK polysaccharide and NSK powder to investigate the bioactivity on the gut microbiota of C57BL/6j mice, respectively. By 16S ribosomal RNA gene sequencing, we found the composition of gut microbiota had been changed and differed from each other. However, the abundance of Bacteroides, Parabacteroides, Escherichia-Shigella and Parasutterella on genus level were significantly increased by NSK polysaccharide and NSK powder. In addition, Akkermansia and Rikenellaceae were enriched by NSK powder. Moreover, we found the IL-1β and IL-6 decreased significantly while TNF-α and IL-10 increased significantly especially in NSK powder group. Intriguingly, the increased microbes were significantly positively co-related with TNF-α and IL-10 while negatively co-related with IL-1β and IL-6 by co-relation and network analysis. The above results suggested that Nostoc sphaeroids Kütz may selectively enrich a "core bacterial community" and add new evidence to discover how Nostoc sphaeroids Kütz has biological function.