Pu-erh tea alleviated colitis-mediated brain dysfunction by promoting butyric acid production

Uncovering the effects and mechanisms of tea and its components on depression, anxiety, and sleep disorders: A comprehensive review

Depression, anxiety and sleep disorders are prevalent psychiatric conditions worldwide, significantly impacting the physical and mental well-being of individuals. The treatment of these conditions poses various challenges, including limited efficacy and potential side effects. Tea, a globally recognized healthful beverage, contains a variety of active compounds. Studies have shown that consuming tea or ingesting its certain active ingredients have a beneficial impact on the mental health issues mentioned above. While the effects of tea on physical health are well-documented, there remains a gap in our systematic understanding of its impact on mental health. This article offers a thorough overview of animal, clinical, and epidemiological studies examining tea and its components in the treatment of depression, anxiety, and sleep disorders, and summarizes the associated molecular mechanisms. The active ingredients in tea, including L-theanine, γ-aminobutyric acid (GABA), arginine, catechins, theaflavins, caffeine, theacrine, and several volatile compounds, may help improve depression, anxiety, and sleep disorders. The underlying molecular mechanisms involve the regulation of neurotransmitters, including monoamines, GABA, and brain-derived neurotrophic factor (BDNF), as well as the suppression of oxidative stress and inflammation. Additionally, these ingredients may influence the microbiota-gut-brain (MGB) axis and the hypothalamic-pituitary-adrenal (HPA) axis. This review provides valuable insights into the effects and mechanisms by which tea and its components regulate depression, anxiety, and sleep disorders, laying the groundwork for further research into relevant mechanisms and the development of tea-based mental health products.

Effects of Different Types and Ratios of Dry Tea Residues on Nutrient Content, In Vitro Rumen Fermentation, and the Bacterial Community of Ensiled Sweet Sorghum

Dry tea residue is a byproduct generated during the production, processing, and storage of tea leaves. The active ingredients and microbial composition of dried tea residue vary depending on different tea processing techniques. This study investigated the effects of six processed dry tea residues-green tea (G), black tea (B), raw Pu'er tea (Z), white tea (W), and ripe Pu'er tea (D)-at two addition ratios (5% and 10%) on the nutritional composition, fermentation quality, in vitro fermentation, and bacterial community of sweet sorghum (Sorghum bicolor) in the ensiling process. Compared to the control group (CK), the addition of tea residue significantly increased the crude protein (CP) content in silage by 17.9% to 180% (p < 0.05), and the content increased with increasing ratios of tea residue. The G10 treatment resulted in the highest CP content, reaching 16.4%. Including tea residue also influenced the ratio of ammonia nitrogen (NH3-N) to non-protein nitrogen (NPN). Furthermore, the G and Z treatments at both addition levels increased the total phenolic content, DPPH free-radical scavenging activity, and total antioxidant capacity of the sweet sorghum silage. Except for the Z5 and W10 treatments, the addition of tea residue did not significantly affect in vitro dry matter digestibility. Overall, this study showed that incorporating tea residue could enhance the nutritional quality and antioxidant capacity of sweet sorghum silage, and the G5 treatment performed the best. The research results suggested that dried tea residues have potential as silage additives.

Intestinal and hepatic benefits of BBR-EVO on DSS-induced experimental colitis in mice

Ulcerative colitis (UC), characterized by disrupted intestinal barrier integrity and chronic inflammation, was modeled in mice via dextran sulfate sodium (DSS) induction. This study explored the therapeutic potential of berberine-evodiamine (BBR-EVO), bioactive components of the traditional Chinese medicine Yulian decoction, in DSS colitis. BBR-EVO intervention ameliorated weight loss, diarrhea, colonic shortening, and histopathological damage in colitic mice. The substance increased antioxidant activity while reducing high levels of pro-inflammatory cytokines in the colon, including as TNF-α, IL-1β, and IL-6. BBR-EVO inhibited the DSS-induced decrease in the tight junction proteins ZO-1 and occludin, according to immunohistochemistry. 16S rRNA sequencing demonstrated BBR-EVO partially attenuated DSS-elicited intestinal dysbiosis, reducing opportunistic pathogens and restoring diminished beneficial taxa. Critically, BBR-EVO alleviated secondary hepatic injury in colitic mice, mitigating immune cell infiltration, oxidative stress, cytokine production, and ultrastructural damage, likely by beneficially modulating gut-liver crosstalk. This study reveals BBR-EVO, derived from a traditional Chinese medicine, confers multi-target protective effects in experimental colitis and associated hepatic pathology, warranting further evaluation as a potential therapy for inflammatory bowel diseases like UC. The mechanisms may involve simultaneous augmentation of intestinal barrier integrity, inhibition of inflammation, microbiota regulation, and gut-liver axis optimization.

Digestive characteristics of Gastrodia elata Blume polysaccharide and related impacts on human gut microbiota in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrodia elata Blume is a traditional Chinese medicine with the effects of improving the deficiency of the body and maintaining health, and polysaccharide (GEP) is one of the effective ingredients to play these activities of G. elata. Traditionally, G. elata is orally administered, so the activities of GEP are associated with digestive and intestinal metabolism. However, the digestive behavior of GEP and its effects on the human gut microbiota are unclear and need to be fully studied.

AIM OF THE STUDY

This study aimed to investigate the changes in structural characteristics of GEP during digestion and the related impacts of its digestive product on gut microbiota in human fecal fermentation, and to explain the beneficial mechanism of GEP on human health from the perspective of digestive characteristics and "gut" axis.

MATERIALS AND METHODS

The changes of reducing sugars, free monosaccharides and physicochemical properties of GEP during digestion were investigated by GPC, HPLC, FT-IR, CD, NMR, SEM, and TGA. Moreover, polysaccharide consumption, pH value changes, SCFAs production, and changes in gut microbiota during fermentation were also discussed.

RESULTS

During digestion of GEP, glucose was partially released causing a decrease in molecular weight, and a change in monosaccharide composition. In addition, the characteristics of GEP before and after digestion, including configuration, morphology, and stability, were different. The digestive product of GEP was polysaccharide (GEP-I), which actively participated in the fecal fermentation process. As the fermentation time increased, the utilization of GEP-I by the microbiota gradually increased. The abundance of probiotics such as Bifidobacterium, Collinsella, Prevotella, and Faecalibacterium was significantly increased, and the abundance of pathogenic Shigella, Dorea, Desulfovibrio, and Blautia was significantly inhibited, thereby suggesting that GEP has the potential to maintain human health through the "gut" axis. In addition, the beneficial health effects of GEP-I have also been observed in the influence of microbial metabolites. During the fermentation of GEP-I, the pH value gradually decreased, and the contents of beneficial metabolites such as acetic acid, propionic acid, and caproic acid significantly increased.

CONCLUSION

The structure of GEP changed significantly during digestion, and its digestive product had the potential to maintain human health by regulating gut microbiota, which may be one of the active mechanisms of GEP.

Therapeutic Effects of Plant Anthocyanin against Alzheimer's Disease and Modulate Gut Health, Short-Chain Fatty Acids

Alzheimer's disease (AD) is the most common form of dementia and neurogenerative disease (NDD), and it is also one of the leading causes of death worldwide. The number of AD patients is over 55 million according to 2020 Alzheimer's Disease International (ADI), and the number is increasing drastically without any effective cure. In this review, we discuss and analyze the potential role of anthocyanins (ACNs) against AD while understanding the molecular mechanisms. ACNs have been reported as having neuroprotective effects by mitigating cognitive impairments, apoptotic markers, neuroinflammation, aberrant amyloidogenesis, and tauopathy. Taken together, ACNs could be an important therapeutic agent for combating or delaying the onset of AD.

Bioactive components and mechanisms of Pu-erh tea in improving levodopa metabolism in rats through COMT inhibition

Catechol-O-methyltransferase (COMT) plays a central role in the metabolic inactivation of endogenous neurotransmitters and xenobiotic drugs and hormones having catecholic structures. Its inhibitors are used in clinical practice to treat Parkinson's disease. In this study, a fluorescence-based visualization inhibitor screening method was developed to assess the inhibition activity on COMT both in vitro and in living cells. Following the screening of 94 natural products, Pu-erh tea extract exhibited the most potent inhibitory effect on COMT with an IC50 value of 0.34 μg mL-1. In vivo experiments revealed that Pu-erh tea extract substantially hindered COMT-mediated levodopa metabolism in rats, resulting in a significant increase in levodopa levels and a notable decrease in 3-O-methyldopa in plasma. Subsequently, the chemical components of Pu-erh tea were analyzed using UHPLC-Q-Exactive Orbitrap HRMS, identifying 24 major components. Among them, epigallocatechin gallate, gallocatechin gallate, epicatechin gallate, and catechin gallate exhibited potent inhibition of COMT activity with IC50 values from 93.7 nM to 125.8 nM and were the main bioactive constituents in Pu-erh tea responsible for its COMT inhibition effect. Inhibition kinetics analyses and docking simulations revealed that these compounds competitively inhibit COMT-mediated O-methylation at the catechol site. Overall, this study not only explained how Pu-erh tea catechins inhibit COMT, suggesting Pu-erh tea as a potential dietary intervention for Parkinson's disease, but also introduced a new strategy for discovering COMT inhibitors more effectively.

Possible Mechanisms of Dark Tea in Cancer Prevention and Management: A Comprehensive Review

Tea is one of the most popular drinks in the world. Dark tea is a kind of post-fermented tea with unique sensory characteristics that is produced by the special fermentation of microorganisms. It contains many bioactive substances, such as tea polyphenols, theabrownin, tea polysaccharides, etc., which have been reported to be beneficial to human health. This paper reviewed the latest research on dark tea's potential in preventing and managing cancer, and the mechanisms mainly involved anti-oxidation, anti-inflammation, inhibiting cancer cell proliferation, inducing cancer cell apoptosis, inhibiting tumor metastasis, and regulating intestinal flora. The purpose of this review is to accumulate evidence on the anti-cancer effects of dark tea, the corresponding mechanisms and limitations of dark tea for cancer prevention and management, the future prospects, and demanding questions about dark tea's possible contributions as an anti-cancer adjuvant.