[Bioactive compounds in the nutrition of peri- and postmenopausal women within the concept of 4P-medicine].

An updated consensus statement from the European Menopause and Andropause Society noted that a woman's quality of life may decline during peri- and post-menopause as a result of various menopausal symptoms and age-related comorbidities. The purpose of the work was to assess the possibility of using bioactive compounds in periand postmenopausal women to prevent the development of menopausal complications and chronic diseases associated with aging. Material and methods. Literature search was carried out using PubMed, Google Scholar, ResearchGate, RSCI databases mainly over the past 10 years, with the exception of works of fundamental importance, according to the keywords "perimenopause", "postmenopause", "Affron® saffron extract", "special extract ERr 731". Results. The use of diet, dietary supplements including those containing extracts of saffron (Affron®) and Siberian rhubarb (ERr 731) and their biologically active substances, has a versatile effect on the correction of menopausal disorders due to the impact on various pathogenetic pathways of their development and can be used in women in this period as a phytonutrient support. Conclusion. The combined use of saffron and Siberian rhubarb extracts is promising from the point of view of correcting the female state during peri- and postmenopause, taking into account the pathogenetic moments of the development of menopausal complications and chronic diseases associated with aging.

An Unexpected Alteration Colonic Mucus Appearance in the Constipation Model via an Intestinal Microenvironment.

Due to the lack of research between the inner layers in the structure of colonic mucous and the metabolism of fatty acid in the constipation model, we aim to determine the changes in the mucous phenotype of the colonic glycocalyx and the microbial community structure following treatment with Rhubarb extract in our research. The constipation and treatment models are generated using adult male C57BL/6N mice. We perform light microscopy and transmission electron microscopy (TEM) to detect a Muc2-rich inner mucus layer attached to mice colon under different conditions. In addition, 16S rDNA sequencing is performed to examine the intestinal flora. According to TEM images, we demonstrate that Rhubarb can promote mucin secretion and find direct evidence of dendritic structure-linked mucus structures with its assembly into a lamellar network in a pore size distribution in the isolated colon section. Moreover, the diversity of intestinal flora has noticeable changes in constipated mice. The present study characterizes a dendritic structure and persistent cross-links have significant changes accompanied by the alteration of intestinal flora in feces in models of constipation and pretreatment with Rhubarb extract.

Pharmacokinetics, tissue distribution and excretion of five rhubarb anthraquinones in rats after oral administration of effective fraction of anthraquinones from rheum officinale.

Rhubarb, a famous traditional Chinese medicine, shows a wide range of physiological activities and pharmacological benefits. Rhubarb anthraquinones are perceived as the pharmacologically active compounds of Rhubarb, and understanding metabolism of them is crucial to assure safety and effectiveness of clinical application. In this study, the pharmacokinetics, tissue distribution and excretion of five rhubarb anthraquinones (aloe-emodin, rhein, emodin, chrysophanol, physcion) were systematically investigated after oral administration of rhubarb extract to rats.An HPLC method was developed and validated for quantitation of five rhubarb anthraquinones in rat plasma, tissues, urine and faeces to investigate the Pharmacokinetic characteristics. The results showed that the proposed method was suitable for the quantification of five anthraquinones in plasma, tissue and excreta samples with satisfactory linear (r > 0.99), precision (<10%) and recovery (85.12-104.20%). The plasma concentration profiles showed a quick absorption with the mean Tmax of 0.42-0.75 h and t1/2 of 6.60-15.11 h for five anthraquinones. The analytes were widely distributed in most of the tissues. Approximately 0.13-10.59% and 28.47-81.14% of five anthraquinones were recovered in urine and faeces within 132 h post-dosing, which indicated the major elimination route was faeces excretion.In summary, this study lays a foundation for elucidating the pharmacokinetic rule of rhubarb anthraquinone and the important data can provide reliable scientific resource for further research.

Subchronic oral toxicity study of rhubarb extract in Sprague-Dawley rats.

OBJECTIVE: The study was primarily used to evaluate subchronic oral toxicity of rhubarb extract. METHODS: The rhubarb extract was orally administered to rats at doses of 0.00, 0.65, 1.62 and 4.05 g/kg BW/day for 13 weeks with a recovery period of 4 weeks. The weight and the relative organ weight of the kidney in the 0.65 g/kg BW group were significantly increased but no significant changes were seen in renal histopathology. When the rats received rhubarb extract at 1.62 g/kg BW or above, the relative weight of the spleen and kidney were significantly increased; the kidney was also swollen and black with hydronephrosis. Histologic examination showed that there was an obvious increase in pigment deposition in renal tubular epithelial cells. No toxic related changes were observed in the 0.65 g/kg BW group, even though organ weight was increased and relative ratio to body weight of kidney were observed at 0.65 g/kg BW dosage, no significant renal histopathologic changes were detected at this dose. Based on the current study conditions and results, the no observed adverse effect level (NOAEL) of rhubarb extract in rats is 0.65 g/kg BW/day.

Neuroprotection of rhubarb extract against cerebral ischaemia-reperfusion injury via the gut-brain axis pathway.

BACKGROUND: The gut-brain axis (GBA) plays a central role in cerebral ischaemia-reperfusion injury (CIRI). Rhubarb, known for its purgative properties, has demonstrated protective effects against CIRI. However, it remains unclear whether this protective effect is achieved through the regulation of the GBA. AIM: This study aims to investigate the mechanism by which rhubarb extract improves CIRI by modulating the GBA pathway. METHODS: We identified the active components of rhubarb extract using LC-MS/MS. The model of middle cerebral artery occlusion (MCAO) was established to evaluate the effect of rhubarb extract. We conducted 16S rDNA sequencing and untargeted metabolomics to analyze intestinal contents. Additionally, we employed HE staining, TUNEL staining, western blot, and ELISA to assess intestinal barrier integrity. We measured the levels of inflammatory cytokines in serum via ELISA. We also examined blood-brain barrier (BBB) integrity using Evans blue (EB) penetration, transmission electron microscopy (TEM), western blot, and ELISA. Neurological function scores and TTC staining were utilized to evaluate neurological outcomes. RESULTS: We identified twenty-six active components in rhubarb. Rhubarb extract enhanced α-diversity, reduced the abundance of Enterobacteriaceae, and partially rectified metabolic disorders in CIRI rats. It also ameliorated pathological changes, increased the expressions of ZO-1, Occludin, and Claudin 1 in the colon, and reduced levels of LPS and d-lac in serum. Furthermore, it lowered the levels of IL-1ß, IL-6, IL-10, IL-17, and TNF-α in serum. Rhubarb extract mitigated BBB dysfunction, as evidenced by reduced EB penetration and improved hippocampal microstructure. It upregulated the expressions of ZO-1, Occludin, Claudin 1, while downregulating the expressions of TLR4, MyD88, and NF-κB. Similarly, rhubarb extract decreased the levels of IL-1ß, IL-6, and TNF-α in the hippocampus. Ultimately, it reduced neurological function scores and cerebral infarct volume. CONCLUSION: Rhubarb effectively treats CIRI, potentially by inhibiting harmful bacteria, correcting metabolic disorders, repairing intestinal barrier function, alleviating BBB dysfunction, and ultimately improving neurological outcomes.

Comparative pharmacokinetics of five rhubarb anthraquinones in normal and thrombotic focal cerebral ischemia-induced rats.

A comparative oral pharmacokinetic study of five anthraquinones (aloe-emodin, emodin, rhein, chrysophanol and physcion) from the extract of Rheum palmatum L. was performed in normal and thrombotic focal cerebral ischemia (TFCI)-induced rats. The plasma samples were clarified through solid phase extraction prior to simultaneous determination of the anthraquinones with a validated high-performance liquid chromatography-fluorescence system. The results indicated that the Cmax, t(1/2) and AUC(0-t), of aloe-emodin, rhein, emodin and chrysophanol in TFCI-induced rats were nearly double, whereas the CL values were remarkably decreased (p < 0.05) over those of the normal rats. The plasma drug concentration-time data of five anthraquinones to rats fitted a two-compartment open model. The five anthraquinones in rat plasma were absorbed quickly and eliminated slowly in both groups. The obtained results could be helpful for evaluating the impact of the efficacy and safety of the drug in clinical applications.

Inulin increases the beneficial effects of rhubarb supplementation on high-fat high-sugar diet-induced metabolic disorders in mice: impact on energy expenditure, brown adipose tissue activity, and microbiota.

Consumption of prebiotics and plant-based compounds have many beneficial health effects through modulation of gut microbiota composition and are considered as promising nutritional strategy for the treatment of metabolic diseases. In the present study, we assessed the separated and combined effects of inulin and rhubarb on diet-induced metabolic disease in mice. We showed that supplementation with both inulin and rhubarb abolished the total body and fat mass gain upon high-fat and high-sucrose diet (HFHS) as well as several obesity-associated metabolic disorders. These effects were associated with increased energy expenditure, lower whitening of the brown adipose tissue, higher mitochondria activity and increased expression of lipolytic markers in white adipose tissue. Despite modifications of intestinal gut microbiota and bile acid compositions by inulin or rhubarb alone, combination of both inulin and rhubarb had minor additional impact on these parameters. However, the combination of inulin and rhubarb increased the expression of several antimicrobial peptides and higher goblet cell numbers, thereby suggesting a reinforcement of the gut barrier. Together, these results suggest that the combination of inulin and rhubarb in mice potentiates beneficial effects of separated rhubarb and inulin on HFHS-related metabolic disease and could be considered as nutritional strategy for the prevention and treatment of obesity and related pathologies.

Study on chronic toxicity of rhubarb extract in Sprague-Dawley rats.

Objective: The purpose of this study was to evaluate the safety of rhubarb extract. Methods: SD rats were treated with rhubarb extract at 0, 101, 405 and 1620 mg/kg/day for 52 weeks. food consumption and body weights were recorded. Blood and urine samples were collected for serum biochemical evaluation and urinalysis, and organ tissues were collected for histopathological examination. Results: The rats of 1620 mg/kg group developed diarrhea symptoms with dark brown loose stool after exposure; decreased body weight and increased food consumption were observed in the 1620 mg/kg and 405 mg/kg groups; urine WBC and NIT was significantly increased in the male and female rats of 1620 mg/kg group, and the urine pH was decreased in male rats of 1620 mg/kg group; renal tubular pigmentation was observed in the 1620 mg/kg group. Conclusion: The NOAEL of rhubarb extract on chronic toxicity (52 weeks) of Sprague-Dawley rats was 101 mg/kg in female and 94 mg/kg in male, and the LOAEL was 408 mg/kg in female and 381 mg/kg in male. The target organ of toxicity was the kidney, and the target cells was tubular epithelial cells.

Underlying beneficial effects of Rhubarb on constipation-induced inflammation, disorder of gut microbiome and metabolism.

Background: Constipation is a common syndrome and a worldwide healthy problem. Constipation patients are becoming younger, with a 29.6% overall prevalence in children, which has captured significant attention because of its epigenetic rejuvenation and recurrent episodes. Despite the usage of rhubarb extract to relieve constipation, novel targets and genes implicated in target-relevant pathways with remarkable functionalities should still be sought for. Materials and methods: We established a reliable constipation model in C57B/6N male mice using intragastric administration diphenoxylate, and the eligible subjects received 600 mg/25 g rhubarb extract to alleviate constipation. Resultant constipation was morphological and genetically compared with the specimen from different groups. Results: Constipation mice exhibited thicker muscle layers, higher levels of cytokines, including IL-17 and IL-23, and lower content of IL-22. Bacterial abundance and diversity varied tremendously. Notably, the alterations were reversed following rhubarb extract treatment. Additionally, Constipation also had a substantial impact on short-chain fatty acids (SCFAs), medium- and long-chain fatty acids (MLCFAs), and the expression of SCFA receptors, GPR41 and GPR43. Conclusion: This thesis has provided insight that rhubarb extract promoted the flexibility of collagen fiber, reduced pro-inflammatory cytokines, enhanced anti-inflammatory cytokines, and maintained gut microflora balance with potential impacts on the fatty acid and polyamine metabolism.

Rhubarb extract relieves constipation by stimulating mucus production in the colon and altering the intestinal flora.

BACKGROUND: Constipation, mainly characterized by the difficulty in defecation, is a clinical symptom caused by a variety of factors. It can be manifested as normal or slow colonic transport abnormalities, which can occur alone or concurrently with defecation disorders. As there is not uniform definition and assessment standard, no clear plan could be used for the treatment of constipation. Although rhubarb, a traditional Chinese medicine, plays a therapeutic role in diseases involving constipation symptoms, the detailed mechanism of it in treating constipation remains unclear. METHODS: A model of constipation-induced by diphenoxylate was prepared. Immunofluorescent staining was used to detect the expression of mucin 2 (MUC2), calnexin and chymase in colon. Western blotting was used to detect changes of tryptase and calnexin in the colon. And real-time polymerase chain reaction (PCR) was utilized to detect the changes of immunoglobulin-binding protein (Bip), X-box binding protein 1 (Xbp1) and C/EBP homologous protein (CHOP) of colonic goblet cells in mRNA levels. ELISA and biochemical kits were utilized to detect the changes of MUC2, Trefoil factor 3 (TFF3), acetylcholine, histamine and C-C motif chemokine ligand 5 (CCL5) in the colon. And the changes of colonic mucosa and intestinal flora of constipation model mice caused by rhubarb extract (RE) were analyzed to identify the mechanism of RE on the treatment of constipation. RESULTS: RE promotes the secretion of colonic mucus by recruiting mast cells and enhancing the content of histamine and Ach in the mice colon. In the process, RE causes up-regulation of Bip and CHOP mRNA expression and down-regulation of Xbp1 and Xbp1s mRNA expression that induces ER stress of colonic epithelium associated with changes in the intestinal flora diversity and short-chain fatty acids content. CONCLUSION: RE could relieve constipation by promoting the secretion of colonic mucus via mast cells activation and improving the intestinal microenvironment.

Fabrication of multifunctional Guar gum-silver nanocomposite hydrogels for biomedical and environmental applications.

Poly(acrylamide-co-acrylamidoglycolic acid)/guar gum@ Ag-nanocomposite (AgNC@PAAG) hydrogels has been fabricated by a green protocol utilizing rhubarb stem-extract as bioreductant. The prepared nanocomposites (NCs) are formulated by varying guar gum (GG) polymer and cross-linker content, and used remarkably to study the release of an anticancer drug, 5-fluorouracil (FU). The AgNC@PAAG has demonstrated its potential in bacterial inactivation and p-nitrophenol (PNP) reduction. The AgNC@PAAG hydrogels showed extended FU release time, which was up to 23 h in pH 7.4. The higher zone of inhibition was documented for AgNC@PAAG against B. subtilis and E. coli. It was noticed that, the inhibition activity of AgNC@PAAG, was directly proportional to cross-linker content than the GG polymer. The efficiency of AgNC@PAAG as a nanocatalyst was evaluated for a model reduction reaction of p-nitrophenol (PNP) reduction by aqueous sodium borohydride (NaBH4), with an apparent rate constant of 121.8 × 10-3 min-1 at ambient temperature. The proposed nanocatalysts are reliable and recyclable, demonstrated its catalytic recycle efficacy of 85% after the third successive run. These NCs robust its biological and catalytic activity after embedding silver nanoparticles (AgNPs) by the bioreduction process; these optimized nanocatalysts can be remarkably used in biomedical healthcare sectors and industrial catalysis.

The beneficial influence of rhubarb on 5-fluorouracil-induced ileal mucositis and the combined role of aquaporin-4, tumour necrosis factor-α, nuclear factor-kappa B & matrix metalloproteinase-9 in rat model: histological study.

A 5-fluorouracil (5-FU) is used for cancer treatment despite its cytotoxic sequelae on healthy cells, especially the rapid proliferating ones. Intestinal mucositis is one of the most frequent chemotherapeutic debilitating sequelae. Rhubarb (Rh), an ancient herb, is known for its curing effect on gastrointestinal complications. This study aims to detect the role of aquaporin-4 (AQP-4), tumour necrosis factor-α (TNF-α), nuclear factor-kappa B (NF-κB), and matrix metalloproteinase-9 (MMP-9) in 5-FU-induced ileal histological and biochemical changes and the potential therapeutic effect of Rh water extract on these changes in rats. A 45 rats were divided into 3 groups; control, 5-FU (single intraperitoneal injection of 150 mg/kg/rat) and Rh-treated (oral 20 mg/kg/day/rat for 8 days). The change in animals' weight, incidence of diarrhoea and AQP-4 and TNF-α values in ileal homogenates were measured. Ileal sections were subjected to hematoxylin and eosin stain, periodic acid Schiff (PAS)-reaction and MMP-9, NF-κB and AQP-4 immunohistochemical staining. A 5-FU group revealed marked ileal mucosal damage associated with a significant decrease in the mean body weight, AQP-4 level and area percent of PAS and AQP-4 positive reaction. Significant increase in the mean incidence of diarrhoea, TNF-α value and area percent of MMP-9 and NF-κB was detected. These changes were significantly corrected with Rh administration. A 5-FU resulted in severe ileal mucositis through TNF-α, NF-κB, MMP-9, and AQP-4 disturbances. Rh treatment was highly effective in preventing such mucositis.

The synergism mechanism of Rhubarb Anthraquinones on constipation elucidated by comparative pharmacokinetics of Rhubarb extract between normal and diseased rats.

In the study, it was hypothesized that Rhubarb Anthraquinones synergistically enhanced the purgative effect on constipation rat from the direct and indirect pathway at the same time. A validated HPLC method was successfully applied to elucidate the synergism mechanism from pharmacokinetics aspect after oral administration of Rhubarb extract with a dose of 0.25 g to normal and constipation rats. Comparison of the pharmacokinetic data of normal and constipation rats showed that there were significant differences (p < 0.05) in the main pharmacokinetic parameters. The C max and AUC of emodin in constipation rats were about ten times that of normal rats, while the t 1/2 was remarkably decreased (p < 0.05). However, a significant decrease (p < 0.05) in AUC value for aloe-emodin and rhein was observed in model group compared with normal group. The results may be attributed to the direct action of aloe-emodin and rhein on intestinal cell membranes and the indirect action of emodin on bowel movement through the adjustment by nervous system.