Neuroprotection of macamide in a mouse model of Alzheimer's disease involves Nrf2 signaling pathway and gut microbiota

The underlying mechanisms of macamide's neuroprotective effects in Alzheimer's disease (AD) were investigated in the paper. Macamides are considered as unique ingredients in maca. Improvement effects and mechanisms of macamide on cognitive impairment have not been revealed. In this study, Vina 1.1.2 was used for docking to evaluate the binding abilities of 12 main macamides to acetylcholinesterase (AChE). N-benzyl-(9Z,12Z)-octadecadienamide (M 18:2) was selected to study the following experiments because it can stably bind to AChE with a strong binding energy. The animal experiments showed that M 18:2 prevented the scopolamine (SCP)-induced cognitive impairment and neurotransmitter disorders, increased the positive rates of Nrf2 and HO-1 in hippocampal CA1, improved the synaptic plasticity by maintaining synaptic morphology and increasing the synapse density. Moreover, the contents of IL-1β, IL-6, and TNF-α in the hippocampus, serum, and colon were reduced by M 18:2. Furthermore, M 18:2 promoted colonic epithelial integrity and partially restored the composition of the gut microbiota to normal, including decreased genera Clostridiales_unclassified and Lachnospiraceae_unclassified, as well as increased genera Muribaculaceae_unclassified, Muribaculum, Alistipes, and Bacteroides, which may be the possible biomarkers of cognitive aging. In summary, M 18:2 exerted neuroprotective effects on SCP-induced AD mice possibly via activating the Nrf2/HO-1 signaling pathway and modulating the gut microbiota.

Potential therapeutic natural compounds for the treatment of Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is a complicated neurodegenerative disease with cognitive impairment occurring in the older people, in which extracellular accumulation of β-amyloid and intracellular aggregation of hyperphosphorylated tau are regarded as the prevailing theories. However, the exact AD mechanism has not been determined. Moreover, there is no effective treatment available in phase III trials to eradicate AD, which is imperative to explore novel treatments.

PURPOSE

A number of up-to-date pre-clinical studies on cognitive impairment is beneficial to clarify the pathology of AD. This review recapitulates several advances in AD pathobiology and discusses the neuroprotective effects of natural compounds, such as phenolic compounds, natural polysaccharides and oligosaccharides, peptide, and lipids, underscoring the therapeutic potential for AD.

METHODS

Electronic databases involving PubMed, Web of Science, and Google Scholar were searched up to October 2023. Articles were conducted using the keywords like Alzheimer's disease, pathogenic mechanisms, natural compounds, and neuroprotection.

RESULT

This review summarized several AD pathologies and the neuroprotective effects of natural compounds such as natural polysaccharides and oligosaccharides, peptide, and lipids.

CONCLUSION

We have discussed the pathogenic mechanisms of AD and the effect natural products on neurodegenerative diseases particularly in treating AD. Specifically, we investigated the molecular pathways and links between natural compounds and Alzheimer's disease such as through NF-κB, Nrf2, and mTOR pathway. Further investigation is necessary in exploring the bioactivity and effectiveness of natural compounds in clinical trials, which may provide a promising treatment for AD patients.

A novel neuroprotective peptide YVYAETY identified and screened from Flammulina velutipes protein hydrolysates attenuates scopolamine-induced cognitive impairment in mice

Flammulina velutipes protein hydrolysates are known for their abundant amino acids and excellent developmental values. This study aimed to identify and screen neuroprotective peptides from F. velutipes protein hydrolysates in vitro and validate the protective effects of YVYAETY on memory impairment in scopolamine-induced mice. The F. velutipes protein was hydrolyzed by simulated gastrointestinal digestion, followed by purification through ultrafiltration and gel chromatography. The fraction exhibiting the strongest neuroprotective activity was analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The main identified peptides (SDLKPADF, WNDHYY, YVYAETY, and WFHPLF) effectively mitigated excessive ROS production by increasing SOD and GSH-px activities while inhibiting cell apoptosis and mitochondrial membrane potential (MMP) collapse against oxidative stress in Aβ25-35-induced HT22 cells. By molecular docking, the interaction between peptides and the active site of the Keap1-Kelch domain reveals their capacity to regulate the Keap1/Nrf2/HO-1 pathway. In vitro, the peptide YVYAETY had the best effect and can be further validated in vivo. The behavioral tests showed that YVYAETY improved scopolamine-induced cognitive impairment in mice. YVYAETY also alleviated neuron damage including neuron vacuolation and pyknotic nuclei in the hippocampus. Furthermore, it significantly inhibited oxidative stress and suppressed the activation of the Nrf2 pathway. Therefore, this study revealed that YVYAETY had the potential to serve as a novel neuroprotective agent.

Investigating the association between inflammation mediated by mushroom consumption and mild cognitive impairment in Chinese older adults

Background: Chronic inflammatory stimulation is a major risk factor for mild cognitive impairment. Mushroom consumption and inflammatory factors may play an important role in the pathogenesis of mild cognitive impairment. Additionally, consuming mushrooms can reduce the levels of inflammatory cytokines and preserve cognitive function. Therefore, this study aimed to investigate the relationship between mushroom consumption and serum inflammatory cytokines and mild cognitive impairment (MCI). Methods: Binary logistic regression was used to determine the relationship between mushroom consumption and MCI in 550 participants. Subsequently, mediation analysis was used to analyze the relationship between mushroom consumption, inflammatory factors, and the Montreal Cognitive assessment (MoCA) score in 248 participants. Results: Mushroom consumption was associated with MCI (odds ratio = 0.623, 95% confidence interval = 0.542-0.715, P < 0.001). The association between mushroom intake and MCI was mediated by interleukin-6 (IL-6) and hypersensitive C-reactive protein (hs-CRP), and the MoCA score was 12.76% and 47.59%, respectively. Conclusion: A high intake of mushrooms was associated with a low risk of MCI. Serum inflammatory factors including IL-6 and hs-CRP play a partial mediating role between mushroom intake and the MoCA score, and the underlying mechanism needs to be further explored.

Research progress and future development potential of Flammulina velutipes polysaccharides in the preparation process, structure analysis, biology, and pharmacology: A review

In recent years, Flammulina velutipes (F. velutipes) has attracted consequential attention in various research fields due to its rich composition of proteins, vitamins, amino acids, polysaccharides, and polyphenols. F. velutipes polysaccharides (FVPs) are considered as key bioactive components of F. velutipes, demonstrating multiple physiological activities, including immunomodulatory, anti-inflammatory, and antibacterial properties. Moreover, they offer health benefits such as antioxidant and anti-aging properties, which have exceptionally valuable clinical applications. Polysaccharides derived from different sources exhibit a wide range of biomedical functions and distinct biological activities. The varied biological functions of polysaccharides, coupled with their extensive application in functional foods and clinical applications, have prompted a heightened focus on polysaccharide research. Additionally, the extraction, deproteinization, and purification of FVPs are fundamental to investigate the structure and biological activities of polysaccharides. Therefore, this review provides a comprehensive and systematic overview of the extraction, deproteinization, purification, characterization, and structural elucidation of FVPs. Furthermore, the biological activities and mechanisms of FVPs have been further explored through in vivo and in vitro experiments. This review aims to provide a theoretical foundation and guide future research and development of FVPs.

Structure and immunostimulatory activity studies on two novel Flammulina velutipes polysaccharides: revealing potential impacts of →6)-α-D-Glcp(1→ on the TLR-4/MyD88/NF-κB pathway

Two novel Flammulina velutipes (F. velutipes) polysaccharides, FVPH1 and FVPH2, were isolated and purified after hot water extraction. The structural characterization revealed that the backbone of FVPH1 consisted mainly of →6)-α-D-Glcp(1→, →3,4)-α-D-Galp(1→, →4)-α-L-Fucp(1→, and →4)-β-D-Manp(1→, while the backbone of FVPH2 consisted of →3)-α-D-Galp(1→, →3,4)-α-D-Manp(1→,→6)-α-D-Glcp(1→. The branches of FVPH1 contained →6)-α-D-Glcp(1→ and α-D-Glcp(1→ and the branches of FVPH2 consisted of →3)-α-D-Galp(1→, →6)-α-D-Glcp(1→, and β-L-Fucp(1→. FVPH2 exhibited significantly better immunostimulatory activity than FVPH1 (P < 0.05), as evidenced by the increased expression of NO, IL-1β, IL-6, and TNF-α and pinocytic activity of RAW264.7 cells. As the most abundant structure in the polysaccharides of F. velutipes, the content of →6)-α-D-Glcp(1→ might play a crucial role in influencing the immunostimulatory activity of F. velutipes polysaccharides. The F. velutipes polysaccharide with a lower content of →6)-α-D-Glcp(1→ and a higher branching degree could significantly enhance the immunostimulatory activity of F. velutipes polysaccharides via activating the TLR-4/MyD88/NF-κB pathway more effectively.

Study on the physicochemical properties and antioxidant activities of Flammulina velutipes polysaccharide under controllable ultrasonic degradation based on artificial neural network

The polysaccharide fraction (FVP2) with molecular weight of 1525.09 kDa and intrinsic viscosity of 3.43 dL/g was isolated and purified from Flammulina velutipes (F. velutipes), and the ultrasonic degradation model of FVP2 was established to predict the molecular weight and intrinsic viscosity at the same time based on artificial neural network. FVP2U1 (1149.11 kDa, 1.78 dL/g), FVP2U2 (618.91 kDa, 1.19 dL/g) and FVP2U3 (597.35 kDa, 0.48 dL/g) with different molecular weights or viscosity were produced by this model to explore the effect of ultrasound on the physicochemical properties and antioxidant activity of FVP2. The results showed that ultrasonic treatment did not change the types of characteristic functional groups, monosaccharide composition and glycosidic bond of FVP2, but changed the chemical composition ratio and the degree of polymerization. Under ultrasonic treatment, the intrinsic viscosity of FVP2 still decreased significantly when the molecular weight did not decrease. Compared to other components subjected to ultrasonic degradation, FVP2U1 demonstrated higher molecular weight and viscoelasticity, while exhibiting lower antioxidant activity. In the case of no significant difference in molecular weight and monosaccharide composition, FVP2U3 with lower intrinsic viscosity has stronger hydration ability, higher crystallization index, lower viscoelasticity and stronger antioxidant capacity than FVP2U2.

Schisandra chinensis Bee Pollen Ameliorates Colitis in Mice by Modulating Gut Microbiota and Regulating Treg/Th17 Balance

Colitis is a chronic disease associated with alterations in the composition of gut microbiota. Schisandra chinensis bee pollen extract (SCPE) has been proved to be rich in phenolic compounds and effective in modulating gut microbiota, but its effect on colitis and the underlying mechanism remains unclear. This study investigates the relationship between colitis amelioration and the gut microbiota regulation of SCPE via fecal microbial transplantation (FMT). The results showed that administration of 20.4 g/kg BW of SCPE could primely ameliorate colitis induced by dextran sulfate sodium (DSS) in mice, showing as more integration of colon tissue structure and the colonic epithelial barrier, as well as lower oxidative stress and inflammation levels compared with colitis mice. Moreover, SCPE supplement restored the balance of T regulatory (Treg) cells and T helper 17 (Th17) cells. Gut microbiota analysis showed SCPE treatment could reshape the gut microbiota balance and improve the abundance of gut microbiota, especially the beneficial bacteria (Akkermansia and Lactobacillus) related to the production of short-chain fatty acids and the regulation of immunity. Most importantly, the protection of 20.4 g/kg BW of SCPE on colitis can be perfectly transmitted by fecal microbiota. Therefore, the gut microbiota-SCFAS-Treg/Th17 axis can be the main mechanism for SCPE to ameliorate colitis. This study suggests that SCPE can be a new promising functional food for prevention and treatment of colitis by reshaping gut microbiota and regulating gut immunity.

Molecular Mechanism of Polysaccharides Extracted from Chinese Medicine Targeting Gut Microbiota for Promoting Health

The accumulating evidence revealed that gut microbiota plays an important role in pathological process of disease including obesity, type 2 diabetes mellitus, heart failure, and non-alcoholic fatty liver disease. Polysaccharides extracted from Chinese medicine (CM) can not only alleviate pathological status but also promote health by anti-inflammatory, regulating immunity, lowering blood glucose and lipids, anti-cancer, and anti-oxidation. The alterations of gut microbiota composition and metabolism pathways are the potential mechanisms of CM polysaccharides treatment. In addition, they exert functions through gut-organ axis or play an indirect role by synergistic actions with other drugs or components mediated by gut microbiota. This review summarizes the molecular mechanisms of CM polysaccharides interacted with intestinal microbial inhabitants as potential prebiotics for promoting health.

Flammulina velutipes polysaccharides regulate lipid metabolism disorders in HFD-fed mice via bile acids metabolism

Our recent study demonstrated that the dynamic changes of gut microbiota mediated by Flammulina velutipes polysaccharide (FVP) could effectively regulate the lipid metabolism in high fat diet-fed (HFD-fed) obese mice model. In this paper, further research was carried out by examining the bile acid (BAs) profiles, as well as the BAs metabolic pathways changes in obese mice. Furthermore, the regulatory effect of BAs on lipid metabolism was verified by 3 T3-L1 preadipocyte differentiation model. The FVP administration resulted in lower BAs content in plasma of obese mice. From the qRT-PCR analysis, FVP could relieve cholestasis in obese mice through altering the BAs metabolic pathways, changing the related genes expressions in mice liver and ileum. The cholic acid (CA), chenodeoxycholic acid (CDCA), hyodeoxycholic acid (HDCA) and ursodeoxycholic acid (UDCA) were selected in cell experiment which all reduced the intracellular triglyceride content and increased the expression of AMPKα1 in 3 T3-L1 adipocytes. Furthermore, CA and CDCA were found increased the expression of PPARα. In combination with our previous research, we further confirmed in this paper that the changes of BAs metabolism caused by FVP showed a positive effect on lipid metabolism, both in obese mice and 3 T3-L1 adipocytes.

Polysaccharides: potential bioactive macromolecules for Alzheimer's disease

Alzheimer's disease (AD) is one of the leading causes of death and disability. AD is a devastating disease that has caused an overwhelming burden. However, no disease-modified treatment was discovered. The approval of sodium oligomannate (GV-971) in mild-moderate AD patients has attracted great attention to investigate the role of saccharides in AD. Therefore, summarizing and explaining the role of saccharides in AD is urgent and promising. Recent studies showed that polysaccharides (PSs) potentially benefit AD in vitro and in vivo. PSs could alleviate the pathological damage and improve cognitive symptoms via (1) antagonizing the toxicity of abnormal amyloid-beta and tau proteins; (2) attenuating oxidative stress and proinflammation; (3) rebuilding neuroplasticity. PSs exhibit one-multiple pathological hits of AD. However, a thorough chemical investigation is needed for further study.

The microbiota-gut-brain axis in hippocampus-dependent learning and memory: current state and future challenges

A fundamental shift in neuroscience suggests bidirectional interaction of gut microbiota with the healthy and dysfunctional brain. This microbiota-gut-brain axis has mainly been investigated in stress-related psychopathology (e.g. depression, anxiety). The hippocampus, a key structure in both the healthy brain and psychopathologies, is implicated by work in rodents that suggests gut microbiota substantially impact hippocampal-dependent learning and memory. However, understanding microbiota-hippocampus mechanisms in health and disease, and translation to humans, is hampered by the absence of a coherent evaluative approach. We review the current knowledge regarding four main gut microbiota-hippocampus routes in rodents: through the vagus nerve; via the hypothalamus-pituitary-adrenal-axis; by metabolism of neuroactive substances; and through modulation of host inflammation. Next, we suggest an approach including testing (biomarkers of) the four routes as a function of the influence of gut microbiota (composition) on hippocampal-dependent (dys)functioning. We argue that such an approach is necessary to proceed from the current state of preclinical research to beneficial application in humans to optimise microbiota-based strategies to treat and enhance hippocampal-dependent memory (dys)functions.

Recent advances in quality preservation of postharvest golden needle mushroom (Flammulina velutiper)

The golden needle mushroom (Flammulina velutiper) is one of the most productive mushrooms in the world. However, F. velutiper experiences continuous quality degradation in terms of changes in color and textural characteristics, loss of moisture, nutrition and flavor, and increased microbial populations due to its high respiratory activity during the postharvest phase. Postharvest preservation techniques, including physical, chemical and biological methods, play a vital role in maintaining postharvest quality and extending the shelf life of mushrooms. Therefore, in this study, the decay process of F. velutiper and the factors affecting its quality were comprehensively reviewed. Additionally, the preservation methods (e.g., low-temperature storage, packaging, plasma treatment, antimicrobial cleaning and 1-methylcyclopropene treatment) for F. velutiper used for the last 5 years were compared to provide an outlook on future research directions. Overall, this review aims to provide a reference for developing novel, green and safe preservation techniques for F. velutiper. © 2023 Society of Chemical Industry.

Effects of Flammulina velutipes polysaccharides on gut microbiota composition and metabolism in vitro fermentation

Flammulina velutipes polysaccharides (FVP) exhibit many biological activities, but the effects on gut microflora and metabolism were still unclear. Here, we explored the composition of FVP, their influence on human gut microflora composition and metabolites. FVP were used to vitro fermentation through human fecal inoculums. In addition, 16S rRNA sequencing were used to assess the effects of FVP on the gut microbiota. The metabolic profiles were investigated using untargeted metabolomics approaches in the LC-MS platform. The results showed that FVP was mainly consisted of glucose, mannose, xylose, fucose and galactose. FVP is shown to increase the relative abundances of Bifidobacteriaceae, as well as Bacteroidaceae and remarkably decrease the numbers of genera Lachnospiraceae coupled with Enterococcaceae. The differential metabolites were identified and mainly involved the metabolism of glycerophospholipid, linoleic acid and synthesis of unsaturated fatty acids. FVP may exhibit biological activity function by regulating gut microflora composition and metabolites.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01192-y.

Prebiotic properties of the polysaccharide from Rosa roxburghii Tratt fruit and its protective effects in high-fat diet-induced intestinal barrier dysfunction: A fecal microbiota transplantation study

Polysaccharide from Rosa roxburghii Tratt fruit (RTFP) ameliorates high-fat diet (HFD)-induced colitis in mice. However, it is still unknown whether the gut microbiota can mediate the anti-colitis effects of RTFP in mice. This research aims to investigate the role of gut microbes in modulating RTFP in colitis mice through fecal microbiota transplantation (FMT). The findings demonstrated that RTFP exhibited prebiotic effects on HFD-induced colitis mice. After FMT treatment (transplatation of the microbiota from the fecal sample to each recipient daily), the fecal microbiota of RTFP-treated donor mice remarkably alleviated colitis-related symptoms (e.g., colonic inflammation, loss of body weight, gut microbiota dysbiosis, and loss of barrier integrity) and upregulated the expression of tight junction proteins compared to the HFD-treated donor mice. Overall, RTFP can reduce the severity of HFD-induced colitis by regulating gut microbiota.

Increasing the production of the bioactive compounds in medicinal mushrooms: an omics perspective

Macroscopic fungi, mainly higher basidiomycetes and some ascomycetes, are considered medicinal mushrooms and have long been used in different areas due to their pharmaceutically/nutritionally valuable bioactive compounds. However, the low production of these bioactive metabolites considerably limits the utilization of medicinal mushrooms both in commerce and clinical trials. As a result, many attempts, ranging from conventional methods to novel approaches, have been made to improve their production. The novel strategies include conducting omics investigations, constructing genome-scale metabolic models, and metabolic engineering. So far, genomics and the combined use of different omics studies are the most utilized omics analyses in medicinal mushroom research (both with 31% contribution), while metabolomics (with 4% contribution) is the least. This article is the first attempt for reviewing omics investigations in medicinal mushrooms with the ultimate aim of bioactive compound overproduction. In this regard, the role of these studies and systems biology in elucidating biosynthetic pathways of bioactive compounds and their contribution to metabolic engineering will be highlighted. Also, limitations of omics investigations and strategies for overcoming them will be provided in order to facilitate the overproduction of valuable bioactive metabolites in these valuable organisms.

Neuroprotective effects of polysaccharide from Sparassis crispa on Alzheimer's disease-like mice: Involvement of microbiota-gut-brain axis

Alzheimer's disease (AD) is an irreversible neurodegenerative disease that may cause neurotoxicity and imbalance in gut microbiota. A polysaccharide derived from Sparassis crispa-1 (SCP-1) acts as a neuroprotective agent in vitro. There is, however, no clarity on the mechanism responsible for SCP-1's neuroprotective effects against AD. In this study, C57BL/6J male mice were treated with D-galactose and AlCl₃ to establish an animal model of AD, followed by treatment with SCP-1. As evidenced by behavioral tests and brain pathology, SCP-1 treatment ameliorated learning deficits and defective spatial recognition, reduced amyloidogenesis, and modulated the neurotransmitter levels (γ-aminobutyric acid, glutamate, and acetylcholine) in the brain of AD mice. The results of 16S rRNA sequencing revealed that SCP-1 reshaped the gut microbiota composition, especially by promoting the proliferation of butyrate-producing genera, such as Intestinaimonas, [Eubacterium] ventriosum group, Lachnospiraceae_UCG_010, and Lachnospiraceae_UCG_001, and suppressing the growth of inflammation-related bacteria (i.e., Escherichia/Shigella). Furthermore, SCP-1 significantly attenuated inflammation by reducing the levels of inflammatory cytokines, maintaining intestinal barrier function, inhibiting glial activation, and decreasing the expression of toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB). Collectively, our findings suggest that SCP-1 may prevent the development of AD via modulation of gut microbiota and suppression of inflammation, for a potential application in preventing or managing AD.

The Interaction between Mushroom Polysaccharides and Gut Microbiota and Their Effect on Human Health: A Review

Mushroom polysaccharides are a kind of biological macromolecule extracted from the fruiting body, mycelium or fermentation liquid of edible fungi. In recent years, the research on mushroom polysaccharides for alleviating metabolic diseases, inflammatory bowel diseases, cancers and other symptoms by changing the intestinal microenvironment has been increasing. Mushroom polysaccharides could promote human health by regulating gut microbiota, increasing the production of short-chain fatty acids, improving intestinal mucosal barrier, regulating lipid metabolism and activating specific signaling pathways. Notably, these biological activities are closely related to the molecular weight, monosaccharide composition and type of the glycosidic bond of mushroom polysaccharide. This review aims to summarize the latest studies: (1) Regulatory effects of mushroom polysaccharides on gut microbiota; (2) The effect of mushroom polysaccharide structure on gut microbiota; (3) Metabolism of mushroom polysaccharides by gut microbiota; and (4) Effects of mushroom polysaccharides on gut microbe-mediated diseases. It provides a theoretical basis for further exploring the mechanism of mushroom polysaccharides for regulating gut microbiota and gives a reference for developing and utilizing mushroom polysaccharides as promising prebiotics in the future.

Long-Term Effect of Porcine Brain Enzyme Hydrolysate Intake on Scopolamine-Induced Memory Impairment in Rats

No study has revealed the effect of porcine brain enzyme hydrolysate (PBEH) on memory impairment. We aimed to examine the hypothesis that PBEH intake modulates memory deficits and cognitive behavior in scopolamine (SC)-induced amnesia rats, and its mechanism, including gut microbiota changes, was determined. Sprague–Dawley male rats had intraperitoneal injections of SC (2 mg/kg body weight/day) at 30 min after daily feeding of casein (MD-control), PBEH (7 mg total nitrogen/mL) at 0.053 mL (Low-PBEH), 0.159 mL (Medium-PBEH), 0.478 mL (High-PBEH), or 10 mg donepezil (Positive-control) per kilogram body weight per day through a feeding needle for six weeks. The Normal-control rats had casein feeding without SC injection. PBEH dose-dependently protected against memory deficits determined by passive avoidance test, Y-maze, water-maze, and novel object recognition test in SC-induced rats compared to the MD-control. The High-PBEH group had a similar memory function to the Positive-control group. Systemic insulin resistance determined by HOMA-IR was lower in the PBEH groups than in the Normal-control but not the Positive-control. In parallel with systemic insulin resistance, decreased cholesterol and increased glycogen contents in the hippocampus in the Medium-PBEH and High-PBEH represented reduced brain insulin resistance. PBEH intake prevented the increment of serum TNF-α and IL-1β concentrations in the SC-injected rats. Hippocampal lipid peroxide and TNF-α contents and mRNA TNF-α and IL-1β expression were dose-dependently reduced in PBEH and Positive-control. PBEH decreased the hippocampal acetylcholinesterase activity compared to the MD-control, but not as much as the Positive-control. PBEH intake increased the α-diversity of the gut microbiota compared to the MD-control, and the gut microbiota community was separated from MD-control. In metagenome function analysis, PBEH increased the energy metabolism-related pathways of the gut microbiota, including citric acid cycle, oxidative phosphorylation, glycolysis, and amino acid metabolism, which were lower in the MD-control than the Normal-control. In conclusion, alleviated memory deficit by PBEH was associated potentially with not only reducing acetylcholinesterase activity but also improving brain insulin resistance and neuroinflammation potentially through modulating gut microbiota. PBEH intake (1.5–4.5 mL of 7 mg total nitrogen/mL for human equivalent) can be a potential therapeutic agent for improving memory impairment.

Potential for non-starch polysaccharides in the prevention and remediation of cognitive impairment: A comprehensive review

Non-starch polysaccharides (NSPs) are food ingredients proven to be beneficial in a large number of health issues. However, there is no literature systematic review about the effects and corresponding mechanisms of NSPs on the prevention and remediation of cognitive impairment. In this review, studies on prevention and remediation of NSPs for cognitive deficit caused by diseases, menopause, ageing, chronic stress and environmental pollutants were summarized and the corresponding mechanisms were established. The anti-cognitive deficit effects of NSPs were associated with the modulation of amyloid β (Aβ) deposition, p-Tau aggregation, oxidative stress, inflammation, neuron apoptosis, neurogenesis, neurotransmitters, synaptic plasticity, autophagy and gut microbiota. Although the structure-function relationship has not been elucidated, several structural properties of NSPs such as molecular weight, sulfate content, hydroxyl group content, monosaccharide composition and molecular chain linkage might be crucial for the anti-cognitive deficit property. Notably, this review revealed that NSPs had a positive effect on cognitive impairment and proposed the future perspectives for further research on the anti-cognitive dysfunction effects of NSPs.

Polysaccharide Regulation of Intestinal Flora: A Viable Approach to Maintaining Normal Cognitive Performance and Treating Depression

The intestinal tract of a healthy body is home to a large variety and number of microorganisms that will affect every aspect of the host’s life. In recent years, polysaccharides have been found to be an important factor affecting intestinal flora. Polysaccharides are widely found in nature and play a key role in the life activities of living organisms. In the intestinal tract of living organisms, polysaccharides have many important functions, such as preventing the imbalance of intestinal flora and maintaining the integrity of the intestinal barrier. Moreover, recent studies suggest that gut microbes can influence brain health through the brain-gut axis. Therefore, maintaining brain health through polysaccharide modulation of gut flora deserves further study. In this review, we outline the mechanisms by which polysaccharides maintain normal intestinal flora structure, as well as improving cognitive function in the brain via the brain-gut axis by virtue of the intestinal flora. We also highlight the important role that gut microbes play in the pathogenesis of depression and the potential for treating depression through the use of polysaccharides to modulate the intestinal flora.

Synergistic alleviation effects of anchovy hydrolysates-catechin on scopolamine-induced mice memory deficits: the exploration of the potential relationship among gut-brain-axis

Anchovy protein hydrolysates (APH) and catechin (CA) have proved to be effective in memory improvement. However, the enhancing effects of APH-CA conjugates on the memory are little investigated. The underlying mechanism and synergic effects remain unclear. Herein, relationships among memory enhancement, gut microbiota, fecal metabolites, and neurotransmitters of mice regulated by APH-CA were investigated. APH, APH-CA, and CA decreased MDA, IL-1β, and TNF-α in liver, altered levels of GPx, LDH, IL-1β, and TNF-α in serum, re-structured gut microbiota, regulated fecal metabolites, and regulated neurotransmitters in the brain. The alleviation effects of APH-CA were partially better than those of APH and CA. The 16s rRNA results illustrated that Bacteroidetes and Firmicutes were altered. Notably, memory-related metabolites and neurotransmitters were significantly up-regulated by the administration of samples. Moreover, possible connections are observed among the gut microbiota, fecal metabolites, and brain neurotransmitters. Together, the regulation of the microbiota-metabolites-brain-neurotransmitters axis may be one of the mechanisms for APH-CA against scopolamine-induced cognitive deficits. In addition, the synergic effects of APH and CA were partially confirmed.

Modulatory effects of polysaccharides from plants, marine algae and edible mushrooms on gut microbiota and related health benefits: A review

Naturally occurring carbohydrate polymers containing non-starch polysaccharides (NPs) are a class of biomacromolecules isolated from plants, marine algae, and edible mushrooms, and their biological activities has shown potential uses in the prevention and treatment of human diseases. Importantly, NPs serve as prebiotics to provide health benefits to the host through stimulating the proliferation of beneficial gut microbiota (GM) and enhancing the production of short-chain fatty acids (SCFAs). The composition and diversity of GM play a critical role in regulating host health and have been extensively studied in recent years. In this review, the extraction, isolation, purification, and structural characterization of NPs derived from plants, marine algae, and edible mushrooms are outlined. Importantly, the degradation and metabolism of these NPs in the intestinal tract, the effects of NPs on the microbial community and SCFAs generation, and the beneficial effects of NPs on host health by modulating GM are systematically highlighted. Overall, we hope that this review can provide some theoretical references and a new perspective for applications of NPs as prebiotics in functional food and drug development.

Purification, structural characterization and neuroprotective effect of a neutral polysaccharide from Sparassis crispa

In the present study, a purified polysaccharide (named SCP-1, Mw 1.368 × 10⁴ Da) was isolated from Sparassis crispa, and its biological activity was evaluated in an oxidative stress model caused by H₂O₂ in hippocampal neuronal HT22 cells. SCP-1 was a heteropolysaccharide mainly comprising glucose, galactose, fucose, and mannose in a molar ratio of 52.10: 31.10: 15.04: 1.76. The main backbone of SCP-1 was predominantly composed of (1→6)-α-_D-Galp, (1→6)-β-_D-Glcp, (1→3)-β-_D-Glcp, (1→2,6)-α-_D-Galp and (1→3,6)-β-_D-Glcp. The branches, substituted at the O-2 of Gal and O-3 of Glc, contained (1→6)-2-OMe-α-_D-Galp, (1→4)-β-_D-Glcp, (1→3)-β-_D-Glcp, and terminated by T-α-_L-Fucp and T-β-_D-Glcp. Besides, SCP-1 could effectively protect the HT22 cells against H₂O₂-induced oxidative injury via decreasing the intracellular reactive oxygen species levels, modulating antioxidant enzymes, and reducing cell apoptosis. The findings suggested that SCP-1 holds a potential to be a natural antioxidant or as a neuroprotective agent.

Effects of ultrasound on the degradation kinetics, physicochemical properties and prebiotic activity of Flammulina velutipes polysaccharide

The controllable ultrasonic modification was hindered due to the uncertainty of the relationship between ultrasonic parameters and polysaccharide quality. In this study, the ultrasonic degradation process was established with kinetics. The physicochemical properties and prebiotic activity of ultrasonic degraded Flammulina velutipes polysaccharides (U-FVPs) were investigated. The results showed that the ultrasonic degradation kinetic models were fitted to 1/M_t-1/M₀ = kt. When the ultrasonic intensity increased from 531 to 3185 W/cm², the degradation proceeded faster. The decrease of polysaccharide concentration contributed to the degradation of FVP, and the fastest degradation rate was at 60 °C. Ultrasound changed the solution conformation of FVP, and partially destroyed the stability of the triple helix structure of FVP. Additionally, the viscosity and gel strength of FVP decreased, but its thermal stability was improved by ultrasound. Higher ultrasonic intensity led to larger variations in physicochemical properties. Compared with FVP, U-FVPs could be more easily utilized by gut microbiota. U-FVPs displayed better prebiotic activity by promoting the growth of Bifidobacterium and Brautella and inhibiting the growth of harmful bacteria. Ultrasound could be effectively applied to the degradation of FVP to improve its physicochemical properties and bioactivities.

The Effects of Consuming White Button Mushroom Agaricus bisporus on the Brain and Liver Metabolome Using a Targeted Metabolomic Analysis

A targeted metabolomic analysis was performed on tissues derived from pigs fed diets supplemented with white button mushrooms (WBM) to determine the effect on the liver and brain metabolome. Thirty-one pigs were fed a grower diet alone or supplemented with either three or six servings of freeze-dried WBM for six weeks. Tissue metabolomes were analyzed using targeted liquid chromatography-mass spectrometry (LC-MS) combined with chemical similarity enrichment analysis (ChemRICH) and correlated to WBM-induced changes in fecal microbiome composition. Results indicated that WBM can differentially modulate metabolites in liver, brain cortex and hippocampus of healthy pigs. Within the glycero-phospholipids, there was an increase in alkyl-acyl-phosphatidyl-cholines (PC-O 40:3) in the hippocampus of pigs fed six servings of WBM. A broader change in glycerophospholipids and sphingolipids was detected in the liver with a reduction in several lipid species in pigs fed both WBM diets but with an increase in amino acids known as precursors of neurotransmitters in the cortex of pigs fed six servings of WBM. Metabolomic changes were positively correlated with increased abundance of Cryomorphaceae, Lachnospiraceae, Flammeovirgaceae and Ruminococcaceae in the microbiome suggesting that WBM can also positively impact tissue metabolite composition.

Isolation, characterization and HepG-2 inhibition of a novel proteoglycan from Flammulina velutipes

Flammulina velutipes has anti-inflammatory, immunomodulatory, antioxidant and many bioactive properties with high contents of carbohydrate, proteins and fibers. In this study, a novel proteoglycan with polysaccharide complexes and protein chain, named PGD1-1, was isolated from F. velutipes. The structural characteristics of PGD1-1 were then determined, and its anti-proliferation and pro-apoptotic activities against HepG-2 cells were demonstrated in vitro. Results proved that the average molecular weight of PGD1-1 was 32.71 kDa, and the carbohydrate and protein contents were 93.35 and 2.33%, respectively. The protein moiety was bonded to a polysaccharide chain via O-glycosidic linkage. The monosaccharides consisted of d-glucose, D-galactose and D-xylose in a molar ratio of 21.90:2.84:1.00. PGD1-1 significantly inhibited the proliferation of HepG-2 cells by affecting cell lipid peroxidation and nitric oxide production. In addition, PGD1-1 promoted the apoptosis of HepG-2 cells, especially the early apoptosis. These findings proved that PGD1-1 was a novel potent ingredient against the proliferation of HepG-2, which will provide a theoretical basis for the development and utilization of the functional ingredients of the F. velutipes.

Whole-plant foods and their macromolecules: untapped approaches to modulate neuroinflammation in Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder. Recently, sustained neuroinflammatory response in microglia and astrocytes has been found to cause the deposition of amyloid beta plaques and the hyperphosphorylation of tau protein, thereby accelerating AD progression. The lipoxin A4-transcription factor nuclear factor-kappa B and mitogen-activated protein kinase pathways have been shown to play important roles in the regulation of inflammatory processes. There is growing research-based evidence suggesting that dietary whole-plant foods, such as mushrooms and berries, may be used as inhibitors for anti-neuroinflammation. The beneficial effects of whole-plant foods were mainly attributed to their high contents of functional macromolecules including polysaccharides, polyphenols, and bioactive peptides. This review provides up-to-date information on important molecular signaling pathways of neuroinflammation and discusses the anti-neuroinflammatory effects of whole-plant foods. Further, a critical evaluation of plants' macromolecular components that have the potential to prevent and/or relieve AD is provided. This work will contribute to better understanding the pathogenetic mechanism of neuroinflammation in AD and provide new approaches for AD therapy.

Dynamic Changes in Microbiome Composition Following Mare's Milk Intake for Prevention of Collateral Antibiotic Effect

Introduction

Probiotics and prebiotics are widely used for recovery of the human gut microbiome after antibiotic treatment. High antibiotic usage is especially common in children with developing microbiome. We hypothesized that dry Mare’s milk, which is rich in biologically active substances without containing live bacteria, could be used as a prebiotic in promoting microbial diversity following antibiotic treatment in children. The present pilot study aims to determine the impacts of dry Mare’s milk on the diversity of gut bacterial communities when administered during antibiotic treatment and throughout the subsequent recovery phase.

Methods

Six children aged 4 to 5 years and diagnosed with bilateral bronchopneumonia were prescribed cephalosporin antibiotics. During the 60 days of the study, three children consumed dry Mare’s milk whereas the other three did not. Fecal samples were collected daily during antibiotic therapy and every 5 days after antibiotic therapy. Total DNA was isolated and taxonomic composition of gut microbiota was analyzed by 16S rRNA amplicon sequencing. To assess the immune status of the gut, stool samples were analyzed by bead-based multiplex assays.

Results

Mare’s milk treatment seems to prevent the bloom of Mollicutes, while preventing the loss of Coriobacteriales. Immunological analysis of the stool reveals an effect of Mare’s milk on local immune parameters under the present conditions.

Health benefits of edible mushroom polysaccharides and associated gut microbiota regulation

Edible mushrooms have been an important part of the human diet for thousands of years, and over 100 varieties have been cultivated for their potential human health benefits. In recent years, edible mushroom polysaccharides (EMPs) have been studied for their activities against obesity, inflammatory bowel disease (IBD), and cancer. Particularly, accumulating evidence on the exact causality between these health risks and specific gut microbiota species has been revealed and characterized, and most of the beneficial health effects of EMPs have been associated with its reversal impacts on gut microbiota dysbiosis. This demonstrates the key role of EMPs in decreasing health risks through gut microbiota modulation effects. This review article compiles and summarizes the latest studies that focus on the health benefits and underlying functional mechanisms of gut microbiota regulation via EMPs. We conclude that EMPs can be considered a dietary source for the improvement and prevention of several health risks, and this review provides the theoretical basis and technical guidance for the development of novel functional foods with the utilization of edible mushrooms.

Investigating causality with fecal microbiota transplantation in rodents: applications, recommendations and pitfalls

In recent years, studies investigating the role of the gut microbiota in health and diseases have increased enormously - making it essential to deepen and question the research methodology employed. Fecal microbiota transplantation (FMT) in rodent studies (either from human or animal donors) allows us to better understand the causal role of the intestinal microbiota across multiple fields. However, this technique lacks standardization and requires careful experimental design in order to obtain optimal results. By comparing several studies in which rodents are the final recipients of FMT, we summarize the common practices employed. In this review, we document the limitations of this method and highlight different parameters to be considered while designing FMT Studies. Standardizing this method is challenging, as it differs according to the research topic, but avoiding common pitfalls is feasible. Several methodological questions remain unanswered to this day and we offer a discussion on issues to be explored in future studies.

Advances in the extraction, purification, structural-property relationships and bioactive molecular mechanism of Flammulina velutipes polysaccharides: A review

With the further research in recent years, Flammulina velutipes (F. velutipes), an edible mushroom, has great application value in many fields. As one of the main bioactive components in F. velutipes, polysaccharide has a series of functions such as anti-oxidation, immune regulation, anti-inflammation, liver protection, anti-tumor, anti-hyperlipidemia and so on. In this paper, the current progress in the extraction, purification, structural characteristics and bioactivities of F. velutipes polysaccharides (FVPs) were reviewed. Meanwhile, the structural-property relationships of FVPs were further discussed. In addition, based on in vitro and in vivo experiments, the possible mechanisms of bioactivities of FVPs were summarized. In order to understand FVPs more comprehensively, the application status and the future research work of FVPs were also introduced. Finally, we hope that our research can provide a reference for further research and development of FVPs.

Silymarin and neurodegenerative diseases: Therapeutic potential and basic molecular mechanisms

BACKGROUND

Neurodegenerative diseases (NDDs) are primarily characterized by selective neuronal loss in the brain. Alzheimer's disease as the most common NDDs and the most prevalent cause of dementia is characterized by Amyloid-beta deposition, which leads to cognitive and memory impairment. Parkinson's disease is a progressive neurodegenerative disease characterized by the dramatic death of dopaminergic neuronal cells, especially in the SNc and caused alpha-synuclein accumulation in the neurons. Silymarin, an extract from seeds of Silybum marianum, administered mostly for liver disorders and also had anti-oxidant and anti-carcinogenic activities.

PURPOSE

The present comprehensive review summarizes the beneficial effects of Silymarin in-vivo and in-vitro and even in animal models for these NDDs.

METHODS

A diagram model for systematic review is utilized for this search. The research is conducted in the following databases: PubMed, Web of Science, Scopus, and Science Direct.

RESULTS

Based on the inclusion criteria, 83 studies were selected and discussed in this review.

CONCLUSION

Lastly, we review the latest experimental evidences supporting the potential effects of Silymarin, as a neuroprotective agent in NDDs.

Genome-wide analysis and prediction of genes involved in the biosynthesis of polysaccharides and bioactive secondary metabolites in high-temperature-tolerant wild Flammulina filiformis

Background

Flammulina filiformis (previously known as Asian F. velutipes) is a popular commercial edible mushroom. Many bioactive compounds with medicinal effects, such as polysaccharides and sesquiterpenoids, have been isolated and identified from F. filiformis, but their biosynthesis and regulation at the molecular level remains unclear. In this study, we sequenced the genome of the wild strain F. filiformis Liu355, predicted its biosynthetic gene clusters (BGCs) and profiled the expression of these genes in wild and cultivar strains and in different developmental stages of the wild F. filiformis strain by a comparative transcriptomic analysis.

Results

We found that the genome of the F. filiformis was 35.01 Mb in length and harbored 10,396 gene models. Thirteen putative terpenoid gene clusters were predicted and 12 sesquiterpene synthase genes belonging to four different groups and two type I polyketide synthase gene clusters were identified in the F. filiformis genome. The number of genes related to terpenoid biosynthesis was higher in the wild strain (119 genes) than in the cultivar strain (81 genes). Most terpenoid biosynthesis genes were upregulated in the primordium and fruiting body of the wild strain, while the polyketide synthase genes were generally upregulated in the mycelium of the wild strain. Moreover, genes encoding UDP-glucose pyrophosphorylase and UDP-glucose dehydrogenase, which are involved in polysaccharide biosynthesis, had relatively high transcript levels both in the mycelium and fruiting body of the wild F. filiformis strain.

Conclusions

F. filiformis is enriched in a number of gene clusters involved in the biosynthesis of polysaccharides and terpenoid bioactive compounds and these genes usually display differential expression between wild and cultivar strains, even in different developmental stages. This study expands our knowledge of the biology of F. filiformis and provides valuable data for elucidating the regulation of secondary metabolites in this unique F. filiformis strain.

The role of prebiotics in cognition, anxiety, and depression

The disruption of the gut microbial composition, defined as dysbiosis, has been associated with many neurological disorders with inflammatory components. The alteration of the gut microbiota leads to an increase in pro-inflammatory cytokines that are associated with metabolic diseases (such as obesity and type 2 diabetes), autoimmune arthritis, and neuropsychiatric diseases. Prebiotics are defined as non-digestible carbohydrates and promote the growth of beneficial bacteria such as bifidobacteria and lactobacillus, exert beneficial effects on improving dysbiosis and its associated inflammatory state. Preclinical and clinical data indicated that some prebiotics also have positive impacts on the central nervous system (CNS) due to the modulation of neuroinflammation and thus may have a key role in the modulation of cognitive impairment, anxiety, and depression. The present manuscript reviews the state-of-art of the effects of prebiotics in cognitive impairment, anxiety, and depressive disorders. Data from clinical studies are still scarce, and further clinical trials are needed to corroborate the potential therapeutic cognitive, antidepressant, and anxiolytic of prebiotics. Prebiotics may provide patients suffering from cognitive deficits, depression, and anxiety with a new tool to minimize disease symptoms and increase the quality of life.

Polysaccharide from flammuliana velutipes improves colitis via regulation of colonic microbial dysbiosis and inflammatory responses

The aim of this study is to investigate whether Flammuliana Velutipes Polysaccharide (FVP) could aid in the prevention of colitis. Effect of FVP on colitis was evaluated using dextran sulfate sodium (DSS)-induced colitis in rats. Influence of FVP on the expression of inflammation related biomarkers and signal pathway element of TLR4\NF-κB were assessed. The composition and taxonomy of colonic microbiota were analyzed by 16S rDNA high throughput sequencing, and the concentrations of caecal short fatty chain acids were assessed by chromatography-mass spectrometry. Our results showed that FVP treatment could regulate the colonic microbial dysbiosis and promote the levels of caecal short fatty chain acids, leading to down-regulation of TLR4\NF-κB signal pathway, which finally ameliorate the colitis. Thus, the present study is the first attempt to elucidate the effect of FVP on colitis and support the potential application of FVP as a functional food ingredient or preventive drugs for colitis.

A novel polysaccharide isolated from Flammulina velutipes, characterization, macrophage immunomodulatory activities and its impact on gut microbiota in rats

The structural characteristics of a novel Flammulina velutipes polysaccharide (FVP2) were explored in this study. Besides, immunomodulatory activities of FVP2 on RAW 264.7 cell and its impact on gut microbiota in rats were investigated. FVP2 has a molecular weight of 18.3 kD, and its main components include galactose (19.96%), glucose (60.66%) and mannose (19.38%). By NMR analysis, the main-chain structure consisted of (1 → 3)-linked-β-D-Gal, (1 → 6) -linked-β-D-Gal, (1 → 6)-linked-α-D-Glc and (1 → 3,6)-linked-α-D-Man was identified. Results of the in vitro assays on RAW 264.7 murine macrophage cells showed FVP2 could significantly up-regulate the expression of NO, TNF-α and IL-6. FVP2 was intragastrically administered to rats for 2 weeks. Compared with the control group, two caecal short-chain fatty acids (SCFAs) concentration (isobutyric acid and butyric acid) and the abundance of beneficial microbiota of the FVP2-treated group were significantly increased (p < .05) respectively. The results demonstrated that FVP2 could effectively enhance the level of butyric acid and increase beneficial gut microbiota, which could improve the intestinal barrier function and maintain the intestinal mucosal integrity, suggesting that FVP2 could potentially be an immunomodulators or a functional food to promote intestinal health.

Effects of a β-type glycosidic polysaccharide from Flammulina velutipes on anti-inflammation and gut microbiota modulation in colitis mice

Using the Flammulina velutipes polysaccharide (FVP) extracted from our previous study, herein, we investigated the improvement of this β-type glycosidic polysaccharide in alleviating dextran sodium sulfate-induced ulcerative colitis (UC) in mice.

Allicin Improves Metabolism in High-Fat Diet-Induced Obese Mice by Modulating the Gut Microbiota

Allicin, naturally present in the bulbs of the lily family, has anticancer, blood pressure lowering, blood fat lowering and diabetes improving effects. Recent studies have shown that allicin promotes the browning of white adipocytes and reduces the weight gain of mice induced by high-fat diet. While the gut microbiota has a strong relationship with obesity and energy metabolism, the effect of allicin on weight loss via gut microorganisms is still unclear. In this study, we treated obese mice induced by high-fat diet with allicin to determine its effects on fat deposition, blood metabolic parameters and intestinal morphology. Furthermore, we used high-throughput sequencing on a MiSeq Illumina platform to determine the gut microorganisms’ species. We found that allicin significantly reduced the weight gain of obese mice by promoting lipolysis and thermogenesis, as well as blood metabolism and intestinal morphology, and suppressing hepatic lipid synthesis and transport. In addition, allicin changed the composition of the intestinal microbiota and increased the proportion of beneficial bacteria. In conclusion, our study showed that allicin improves metabolism in high-fat induced obese mice by modulating the gut microbiota. Our findings provide a theoretical basis for further elucidation of the weight loss mechanism of allicin.

Time-dependent gut microbiota analysis of juvenile Oreochromis niloticus by dietary supplementation of resveratrol

To evaluate the changes in bacterial diversity at various time points under resveratrol supplementation, we aimed to investigate the diversification of gut microbiota and the changes in total genetic diversity. We performed 16S rDNA gene sequencing at different time points (15, 30, and 45 days) to analyze the gut microbiota of tilapia. Fusobacteria, Proteobacteria, and Bacteroidetes (15 days) or Cyanobacteria (30 and 45 days) were found to be the three most abundant phyla. Cyanobacteria (15 and 30 days), Proteobacteria (15 days), Firmicutes and Chlamydiae (30 and 45 days), Planctomycetes (30 days), Bacteroidetes, Actinobacteria, and Fusobacteria (45 days) in the 0.05 g/kg RES group increased as compared to that in the controls. Proteobacteria and Cyanobacteria significantly decreased and increased at 30 and 45 days, respectively, while the reverse pattern was observed at 15 days. The Bacteroidetes:Firmicutes and Proteobacteria:Cyanobacteria ratios were significantly increased (15 and 45 days, P < 0.05) and decreased (30 days, P < 0.05). RES supplementation did not affect the richness and diversity of the gut microbiota in tilapia. Our findings may contribute to the development of strategies for the management of diseases.

Gut microbiota in phytopharmacology: A comprehensive overview of concepts, reciprocal interactions, biotransformations and mode of actions

The dynamic and delicate interactions amongst intestinal microbiota, metabolome and metabolism dictates human health and disease. In recent years, our understanding of gut microbial regulation of intestinal immunometabolic and redox homeostasis have evolved mainly out of in vivo studies associated with high-fat feeding induced metabolic diseases. Techniques utilizing fecal transplantation and germ-free mice have been instrumental in reproducibly demonstrating how the gut microbiota affects disease pathogenesis. However, the pillars of modern drug discovery i.e. evidence-based pharmacological studies critically lack focus on intestinal microflora. This is primarily due to targeted in vitro molecular-approaches at cellular-level that largely overlook the etiology of disease pathogenesis from the physiological perspective. Thus, this review aims to provide a comprehensive understanding of the key notions of intestinal microbiota and dysbiosis, and highlight the microbiota-phytochemical bidirectional interactions that affects bioavailability and bioactivity of parent phytochemicals and their metabolites. Potentially by focusing on the three major aspects of gut microbiota i.e. microbial abundance, diversity, and functions, I will discuss phytochemical-microbiota reciprocal interactions, biotransformation of phytochemicals and plant-derived drugs, and pre-clinical and clinical efficacies of herbal medicine on dysbiosis. Additionally, in relation to phytochemical pharmacology, I will briefly discuss the role of dietary-patterns associated with changes in microbial profiles and review pharmacological study models considering possible microbial effects. This review therefore, emphasize on the timely and critically needed evidence-based phytochemical studies focusing on gut microbiota and will provide newer insights for future pre-clinical and clinical phytopharmacological interventions.