RESUMO
Aim: Hyperuricemia (HUA) has received increased attention in the last few decades due to its global prevalence. Our previous study found that administration of a macroporous resin extract of Dendrobium officinale leaves (DoMRE) to rats with HUA that was induced by exposure to potassium oxazine combined with fructose and a high-purine diet led to a significant reduction in serum uric acid (SUA) levels. The aim of this study was to explore the effects of DoMRE on hyperuricemia induced by anthropomorphic unhealthy lifestyle and to elucidate its possible mechanisms of action. Methods: Dosages (5.0 and 10.0 g/kg/day) of DoMRE were administered to rats daily after induction of HUA by anthropomorphic unhealthy lifestyle for 12 weeks. The levels of UA in the serum, urine, and feces; the levels of creatinine (Cr) in the serum and urine; and the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum were all measured using an automatic biochemical analyzer. The activities of xanthine oxidase (XOD) and adenosine deaminase (ADA) in the serum, liver, and intestine tissue supernatant were measured using appropriate kits for each biological target. The expressions levels of UA transporters (ABCG2 and GLUT9), tight junction (TJ) proteins (ZO-1 and occludin), and inflammatory factors (IL-6, IL-8, and TNF-α) in the intestine were assayed by immunohistochemical (IHC) staining. Hematoxylin and eosin (H&E) staining was used to assess histological changes in the renal and intestinal tissues. Results: DoMRE treatment significantly reduced SUA levels and concomitantly increased fecal UA (FUA) levels and the fractional excretion of UA (FEUA) in HUA rats. Furthermore, DoMRE significantly reduced both the XOD activity in the serum, liver, and intestine and the ADA activity in the liver and intestine. DoMRE also effectively regulated the expression of GLUT9 and ABCG2 in the intestine, and it significantly upregulated the expression of the intestinal TJ proteins ZO-1 and occludin. Therefore, DoMRE reduced the damage to the intestinal barrier function caused by the increased production of inflammatory factors due to HUA to ensure normal intestinal UA excretion. Conclusion: DoMRE demonstrated anti-HUA effects in the HUA rat model induced by an anthropomorphic unhealthy lifestyle, and the molecular mechanism appeared to involve the regulation of urate transport-related transporters (ABCG2 and GLUT9) in the intestine, protection of the intestinal barrier function to promote UA excretion, and inhibition of XOD and ADA activity in the liver and intestine to inhibit UA production in the HUA-induced rats.
RESUMO
Sub-health status, in which a person's mind and body exist in a low-quality state of being between disease and health, has become an urgent public health problem that cannot be ignored globally. One of the most apparent sub-health symptoms is fatigue, and it also shows a significant decrease in mental vitality and adaptability caused by disruption of the neuroendocrine-immune system. Dendrobium officinale (DOF) has a long history of use in China as a medicinal food with immune-regulating, anti-fatigue, anti-oxidant, and hypoglycemic effects. The ameliorative effects of Dendrobium officinale on sub-health mice are investigated in this present study, as well as its underlying mechanisms via neuroendocrine-immune (NEI) modulation. Forty male KM mice were divided into normal control group (NC), model control group (MC), and two doses of ultrafine DOF powder (DOFP) intervention groups: DOFP-L (0.1 g kg-1), DOFP-H (0.2 g kg-1) groups. Sub-health mice were induced by mimicking unhealthy human lifestyles, including cold water swimming, limbs restriction, an unhealthy diet, and sleep deprivation for seven weeks. The findings revealed that DOFP intervened sub-health mice have less bodyweight loss, normal fecal morphology, as well as lower face temperature and blood flow, which is similar to the normal mice. Moreover, sub-health mice treated with DOFP showed improved forelimb grip strength and exercise endurance in weight-loaded exhaustion swimming and cold water exhaustion swimming, combined with reduced content of lactic acid (LD), lactate dehydrogenase (LDH), blood urea nitrogen (BUN) in the plasma, increased storage of liver glycogen (LG), and muscle glycogen (MG), as well as increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), reduced malondialdehyde (MDA) levels in the liver. Additionally, DOFP could increase the counts of autonomous movements of sub-health mice, minimize tail suspension time, and perform well in the elevated plus maze and open field tests, all of which are associated with anti-depression and anti-anxiety. Moreover, mechanistic investigations revealed that DOFP could alleviate plasma corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and cortisol (CORT) related hormones in the HPA axis, increase the level of hypothalamic norepinephrine (NE) and plasma ß-endorphin (ß-EP) of sub-health mice, while downregulating the content of 5-hydroxytryptamine (5-HT), dopamine (DA), and the relative mRNA expression of 5-HT1A and CRH in hypothalamus, and increase immunoglobulin G (IgG), immunoglobulin A (IgA), immunoglobulin M (IgM), and CD4+/CD8+ T cell ratio levels. In conclusion, DOFP can relieve symptoms such as fatigue and depression in sub-health mice by regulating the disorder of the neuroendocrine-immune network.
