Zhuifeng Tougu capsules in the treatment of knee osteoarthritis (cold dampness obstruction syndrome): a randomized, double blind, multicenter clinical study.

BACKGROUND: In Traditional Chinese Medicine (TCM) theory, cold dampness obstruction is one of the common syndromes of osteoarthritis. Therefore, in clinical practice, the main treatment methods are to dispel wind, remove dampness, and dissipate cold, used to treat knee osteoarthritis (KOA). This report describes a mulitercenter clinical study to assess Zhuifeng Tougu Capsule's efficacy and safety in the treatment of patients who are cold dampness obstruction syndrome in KOA, and to provide evidence-based medical for the rational use of Zhuifeng Tougu Capsules in clinical practice. METHODS: This randomized, parallel group controlled, double-blind, double dummy trial will include a total of 215 KOA patients who meet the study criteria. 215 patients underwent 1:1 randomisation, with 107 cases assigned the experimental group (Zhuifeng Tougu Capsules + Glucosamine Sulfate Capsules Simulator) and 108 assigned the control group (Glucosamine Sulfate Capsules + Zhuifeng Tougu Capsules Simulator). After enrolment, patients received 12 weeks of treatment. The main efficacy measure is the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) pain score. Visual analogue scale (VAS) pain score, Self-condition assessment VAS score, WOMAC KOA score, TCM syndrome score and TCM syndrome efficacy, ESR level, CRP level, suprapatellar bursa effusion depth, use of rescue drugs, and safety indicators are secondary efficacy indicators. RESULTS: Compared with before treatment, WOMAC pain score, VAS pain score, Self-condition assessment VAS score, WOMAC KOA score, and TCM syndrome score decreased significantly in both groups (P < 0.01). Also, the experimental group showed significant differences in the above indicators compared to control (P < 0.01). However, after treatment, no significant differences were showed in the ESR level, CRP level, and suprapatellar bursa effusion depth between the two groups (P > 0.05). No any serious adverse effects showed in the experimental group and control group. CONCLUSIONS: Zhuifeng Tougu Capsules can effectively improve knee joint function and significantly alleviate the pain of KOA. TRIAL REGISTRATION: Clinical trial registration was completed with the China Clinical Trial Registration Center for this research protocol (No. ChiCTR2000028750) on January 2, 2020.

Anoctamin 4 channel currents activate glucose-inhibited neurons in the mouse ventromedial hypothalamus during hypoglycemia.

Glucose is the basic fuel essential for maintenance of viability and functionality of all cells. However, some neurons - namely, glucose-inhibited (GI) neurons - paradoxically increase their firing activity in low-glucose conditions and decrease that activity in high-glucose conditions. The ionic mechanisms mediating electric responses of GI neurons to glucose fluctuations remain unclear. Here, we showed that currents mediated by the anoctamin 4 (Ano4) channel are only detected in GI neurons in the ventromedial hypothalamic nucleus (VMH) and are functionally required for their activation in response to low glucose. Genetic disruption of the Ano4 gene in VMH neurons reduced blood glucose and impaired counterregulatory responses during hypoglycemia in mice. Activation of VMHAno4 neurons increased food intake and blood glucose, while chronic inhibition of VMHAno4 neurons ameliorated hyperglycemia in a type 1 diabetic mouse model. Finally, we showed that VMHAno4 neurons represent a unique orexigenic VMH population and transmit a positive valence, while stimulation of neurons that do not express Ano4 in the VMH (VMHnon-Ano4) suppress feeding and transmit a negative valence. Together, our results indicate that the Ano4 channel and VMHAno4 neurons are potential therapeutic targets for human diseases with abnormal feeding behavior or glucose imbalance.

Asprosin promotes feeding through SK channel-dependent activation of AgRP neurons.

Asprosin, a recently identified adipokine, activates agouti-related peptide (AgRP) neurons in the arcuate nucleus of the hypothalamus (ARH) via binding to protein tyrosine phosphatase receptor δ (Ptprd) to increase food intake. However, the intracellular mechanisms responsible for asprosin/Ptprd-mediated activation of AgRPARH neurons remain unknown. Here, we demonstrate that the small-conductance calcium-activated potassium (SK) channel is required for the stimulatory effects of asprosin/Ptprd on AgRPARH neurons. Specifically, we found that deficiency or elevation of circulating asprosin increased or decreased the SK current in AgRPARH neurons, respectively. AgRPARH-specific deletion of SK3 (an SK channel subtype highly expressed in AgRPARH neurons) blocked asprosin-induced AgRPARH activation and overeating. Furthermore, pharmacological blockade, genetic knockdown, or knockout of Ptprd abolished asprosin's effects on the SK current and AgRPARH neuronal activity. Therefore, our results demonstrated an essential asprosin-Ptprd-SK3 mechanism in asprosin-induced AgRPARH activation and hyperphagia, which is a potential therapeutic target for the treatment of obesity.

Hypothalamic steroid receptor coactivator-2 regulates adaptations to fasting and overnutrition.

The neuroendocrine system coordinates metabolic and behavioral adaptations to fasting, including reducing energy expenditure, promoting counterregulation, and suppressing satiation and anxiety to engage refeeding. Here, we show that steroid receptor coactivator-2 (SRC-2) in pro-opiomelanocortin (POMC) neurons is a key regulator of all these responses to fasting. POMC-specific deletion of SRC-2 enhances the basal excitability of POMC neurons; mutant mice fail to efficiently suppress energy expenditure during food deprivation. SRC-2 deficiency blunts electric responses of POMC neurons to glucose fluctuations, causing impaired counterregulation. When food becomes available, these mutant mice show insufficient refeeding associated with enhanced satiation and discoordination of anxiety and food-seeking behavior. SRC-2 coactivates Forkhead box protein O1 (FoxO1) to suppress POMC gene expression. POMC-specific deletion of SRC-2 protects mice from weight gain induced by an obesogenic diet feeding and/or FoxO1 overexpression. Collectively, we identify SRC-2 as a key molecule that coordinates multifaceted adaptive responses to food shortage.

Deciphering an AgRP-serotoninergic neural circuit in distinct control of energy metabolism from feeding.

Contrasting to the established role of the hypothalamic agouti-related protein (AgRP) neurons in feeding regulation, the neural circuit and signaling mechanisms by which they control energy expenditure remains unclear. Here, we report that energy expenditure is regulated by a subgroup of AgRP neurons that send non-collateral projections to neurons within the dorsal lateral part of dorsal raphe nucleus (dlDRN) expressing the melanocortin 4 receptor (MC4R), which in turn innervate nearby serotonergic (5-HT) neurons. Genetic manipulations reveal a bi-directional control of energy expenditure by this circuit without affecting food intake. Fiber photometry and electrophysiological results indicate that the thermo-sensing MC4RdlDRN neurons integrate pre-synaptic AgRP signaling, thereby modulating the post-synaptic serotonergic pathway. Specifically, the MC4RdlDRN signaling elicits profound, bi-directional, regulation of body weight mainly through sympathetic outflow that reprograms mitochondrial bioenergetics within brown and beige fat while feeding remains intact. Together, we suggest that this AgRP neural circuit plays a unique role in persistent control of energy expenditure and body weight, hinting next-generation therapeutic approaches for obesity and metabolic disorders.

Zhuifeng Tougu capsules improve rheumatoid arthritis symptoms in rats by regulating the toll-like receptor 2/4-nuclear factor kappa-B signaling pathway.

OBJECTIVE: To investigate the efficacy of Zhuifeng tougu capsules (, ZFTG) in the treatment of rheumatoid arthritis (RA) in rats and study its mechanism, focusing on the toll-like receptor 2/4-nuclear factor kappa-B (TLR2/4-NF-κB) signaling pathway. METHODS: Type Ⅱ collagen and an artificial climate box were used to construct the rat model of collagen-induced arthritis with wind-cold-dampness arthralgia syndrome. The rats were divided randomly into a control group, wind-cold-dampness syndrome model group, and high-, medium-, and low-dose ZFTG groups. The methotrexate (MTX) control group was treated with the corresponding drug intervention for 28 d. The joint temperature, pain threshold, joint swelling degree, and arthritis index (AI) score were measured. The production of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and rheumatoid factors (RFs) in the blood was detected by enzyme-linked immunosorbent assay. The protein expression of TLR2, TLR4, and NF-κB in synovial tissues was detected by Western blotting, and the mRNA expression of TLR2, TLR4, and NF-κB was detected by real-time polymerase chain reaction. RESULTS: Compared with the model group, the joint temperature in each treatment group, the MTX control group, and MTX group recovered, the degree of foot swelling, pain threshold, AI score decreased, serum CRP, ESR, RF level and the levels of TLR2, TLR4, and NF-κB in synovial tissue were decreased (P < 0.05). Among them, the curative effect in the medium-dose and MTX groups was more evident (P < 0.01). CONCLUSION: ZFTG has a significant effect on RA in rats, and its mechanism may involve regulating CRP levels, the ESR, and RFs via the TLR2/4-NF-κB signaling pathway.

Vitamin D actions in neurons require the PI3K pathway for both enhancing insulin signaling and rapid depolarizing effects.

Despite correlations between low vitamin D levels and diabetes incidence/severity, supplementation with vitamin D has not been widely effective in improving glucose parameters. This may be due to a lack of knowledge regarding how low vitamin D levels physiologically affect glucose homeostasis. We have previously shown that the brain may be a critical area for vitamin d-mediated action on peripheral glucose levels. However, the mechanisms for how vitamin D acts in the brain are unknown. We utilized a multimodal approach to determine the mechanisms by which vitamin D may act in the brain. We first performed an unbiased search (RNA-sequencing) for pathways affected by vitamin D. Vitamin D (125-dihydroxyvitamin D3; 1,25D3) delivered directly into the third ventricle of obese animals differentially regulated multiple pathways, including the insulin signaling pathway. The insulin signaling pathway includes PI3K, which is important in the brain for glucose regulation. Since others have shown that vitamin D acts through the PI3K pathway in non-neuronal cells (muscle and bone), we hypothesized that vitamin D may act in neurons through a PI3K-dependent pathway. In a hypothalamic cell-culture model (GT1-7 cells), we demonstrate that 1,25D3 increased phosphorylation of Akt in the presence of insulin. However, this was blocked with pre-treatment of wortmannin, a PI3K inhibitor. 1,25D3 increased gene transcription of several genes within the PI3K pathway, including Irs2 and p85, without affecting expression of InsR or Akt. Since we had previously shown that 1,25D3 has significant effects on neuronal function, we also tested if the PI3K pathway could mediate rapid actions of vitamin D. We found that 1,25D3 increased the firing frequency of neurons through a PI3K-dependent mechanism. Collectively, these data support that vitamin D enhances insulin signaling and neuronal excitability through PI3K dependent processes which involve both transcriptional and membrane-initiated signaling events.

Steroid receptor coactivator-1 modulates the function of Pomc neurons and energy homeostasis.

Hypothalamic neurons expressing the anorectic peptide Pro-opiomelanocortin (Pomc) regulate food intake and body weight. Here, we show that Steroid Receptor Coactivator-1 (SRC-1) interacts with a target of leptin receptor activation, phosphorylated STAT3, to potentiate Pomc transcription. Deletion of SRC-1 in Pomc neurons in mice attenuates their depolarization by leptin, decreases Pomc expression and increases food intake leading to high-fat diet-induced obesity. In humans, fifteen rare heterozygous variants in SRC-1 found in severely obese individuals impair leptin-mediated Pomc reporter activity in cells, whilst four variants found in non-obese controls do not. In a knock-in mouse model of a loss of function human variant (SRC-1L1376P), leptin-induced depolarization of Pomc neurons and Pomc expression are significantly reduced, and food intake and body weight are increased. In summary, we demonstrate that SRC-1 modulates the function of hypothalamic Pomc neurons, and suggest that targeting SRC-1 may represent a useful therapeutic strategy for weight loss.

Loss of function of NCOR1 and NCOR2 impairs memory through a novel GABAergic hypothalamus-CA3 projection.

Nuclear receptor corepressor 1 (NCOR1) and NCOR2 (also known as SMRT) regulate gene expression by activating histone deacetylase 3 through their deacetylase activation domain (DAD). We show that mice with DAD knock-in mutations have memory deficits, reduced anxiety levels, and reduced social interactions. Mice with NCOR1 and NORC2 depletion specifically in GABAergic neurons (NS-V mice) recapitulated the memory deficits and had reduced GABAA receptor subunit α2 (GABRA2) expression in lateral hypothalamus GABAergic (LHGABA) neurons. This was associated with LHGABA neuron hyperexcitability and impaired hippocampal long-term potentiation, through a monosynaptic LHGABA to CA3GABA projection. Optogenetic activation of this projection caused memory deficits, whereas targeted manipulation of LHGABA or CA3GABA neuron activity reversed memory deficits in NS-V mice. We describe de novo variants in NCOR1, NCOR2 or HDAC3 in patients with intellectual disability or neurodevelopmental disorders. These findings identify a hypothalamus-hippocampus projection that may link endocrine signals with synaptic plasticity through NCOR-mediated regulation of GABA signaling.

TAp63 contributes to sexual dimorphism in POMC neuron functions and energy homeostasis.

Sexual dimorphism exists in energy balance, but the underlying mechanisms remain unclear. Here we show that the female mice have more pro-opiomelanocortin (POMC) neurons in the arcuate nucleus of hypothalamus than males, and female POMC neurons display higher neural activities, compared to male counterparts. Strikingly, deletion of the transcription factor, TAp63, in POMC neurons confers "male-like" diet-induced obesity (DIO) in female mice associated with decreased POMC neural activities; but the same deletion does not affect male mice. Our results indicate that TAp63 in female POMC neurons contributes to the enhanced POMC neuron functions and resistance to obesity in females. Thus, TAp63 in POMC neurons is one key molecular driver for the sexual dimorphism in energy homeostasis.

Asprosin is a centrally acting orexigenic hormone.

Asprosin is a recently discovered fasting-induced hormone that promotes hepatic glucose production. Here we demonstrate that asprosin in the circulation crosses the blood-brain barrier and directly activates orexigenic AgRP+ neurons via a cAMP-dependent pathway. This signaling results in inhibition of downstream anorexigenic proopiomelanocortin (POMC)-positive neurons in a GABA-dependent manner, which then leads to appetite stimulation and a drive to accumulate adiposity and body weight. In humans, a genetic deficiency in asprosin causes a syndrome characterized by low appetite and extreme leanness; this is phenocopied by mice carrying similar mutations and can be fully rescued by asprosin. Furthermore, we found that obese humans and mice had pathologically elevated concentrations of circulating asprosin, and neutralization of asprosin in the blood with a monoclonal antibody reduced appetite and body weight in obese mice, in addition to improving their glycemic profile. Thus, in addition to performing a glucogenic function, asprosin is a centrally acting orexigenic hormone that is a potential therapeutic target in the treatment of both obesity and diabetes.

Hypothalamic Vitamin D Improves Glucose Homeostasis and Reduces Weight.

Despite clear associations between vitamin D deficiency and obesity and/or type 2 diabetes, a causal relationship is not established. Vitamin D receptors (VDRs) are found within multiple tissues, including the brain. Given the importance of the brain in controlling both glucose levels and body weight, we hypothesized that activation of central VDR links vitamin D to the regulation of glucose and energy homeostasis. Indeed, we found that small doses of active vitamin D, 1α,25-dihydroxyvitamin D3 (1,25D3) (calcitriol), into the third ventricle of the brain improved glucose tolerance and markedly increased hepatic insulin sensitivity, an effect that is dependent upon VDR within the paraventricular nucleus of the hypothalamus. In addition, chronic central administration of 1,25D3 dramatically decreased body weight by lowering food intake in obese rodents. Our data indicate that 1,25D3-mediated changes in food intake occur through action within the arcuate nucleus. We found that VDR colocalized with and activated key appetite-regulating neurons in the arcuate, namely proopiomelanocortin neurons. Together, these findings define a novel pathway for vitamin D regulation of metabolism with unique and divergent roles for central nervous system VDR signaling. Specifically, our data suggest that vitamin D regulates glucose homeostasis via the paraventricular nuclei and energy homeostasis via the arcuate nuclei.