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Nutrients May 2024Polymethoxyflavonoids, such as nobiletin (abundant in Citrus depressa), have been reported to have antioxidant, anti-inflammatory, anticancer, and anti-dementia effects,...
Polymethoxyflavonoids, such as nobiletin (abundant in Citrus depressa), have been reported to have antioxidant, anti-inflammatory, anticancer, and anti-dementia effects, and are also a circadian clock modulator through retinoic acid receptor-related orphan receptor (ROR) α/γ. However, the optimal timing of nobiletin intake has not yet been determined. Here, we explored the time-dependent treatment effects of nobiletin and a possible novel mechanistic idea for nobiletin-induced circadian clock regulation in mice. In vivo imaging showed that the PER2::LUC rhythm in the peripheral organs was altered in accordance with the timing of nobiletin administration (100 mg/kg). Administration at ZT4 (middle of the light period) caused an advance in the peripheral clock, whereas administration at ZT16 (middle of the dark period) caused an increase in amplitude. In addition, the intraperitoneal injection of nobiletin significantly and potently stimulated corticosterone and adrenaline secretion and caused an increase in expression in the peripheral tissues. Nobiletin inhibited phosphodiesterase (PDE) 4A1A, 4B1, and 10A2. Nobiletin or rolipram (PDE4 inhibitor) injection, but not SR1078 (RORα/γ agonist), caused acute expression in the peripheral tissues. Thus, the present study demonstrated a novel function of nobiletin and the regulation of the peripheral circadian clock.
Topics: Animals; Flavones; Circadian Clocks; Mice; Male; Corticosterone; Period Circadian Proteins; Epinephrine; Mice, Inbred C57BL; Nuclear Receptor Subfamily 1, Group F, Member 1; Circadian Rhythm
PubMed: 38794729
DOI: 10.3390/nu16101491 -
International Journal of Molecular... May 2024Clinical and preclinical studies have provided conflicting data on the postulated beneficial effects of vitamin D in patients with prostate cancer. In this opinion... (Review)
Review
Clinical and preclinical studies have provided conflicting data on the postulated beneficial effects of vitamin D in patients with prostate cancer. In this opinion piece, we discuss reasons for discrepancies between preclinical and clinical vitamin D studies. Different criteria have been used as evidence for the key roles of vitamin D. Clinical studies report integrative cancer outcome criteria such as incidence and mortality in relation to vitamin D status over time. In contrast, preclinical vitamin D studies report molecular and cellular changes resulting from treatment with the biologically active vitamin D metabolite, 1,25-dihydroxyvitamin D (calcitriol) in tissues. However, these reported changes in preclinical in vitro studies are often the result of treatment with biologically irrelevant high calcitriol concentrations. In typical experiments, the used calcitriol concentrations exceed the calcitriol concentrations in normal and malignant prostate tissue by 100 to 1000 times. This raises reasonable concerns regarding the postulated biological effects and mechanisms of these preclinical vitamin D approaches in relation to clinical relevance. This is not restricted to prostate cancer, as detailed data regarding the tissue-specific concentrations of vitamin D metabolites are currently lacking. The application of unnaturally high concentrations of calcitriol in preclinical studies appears to be a major reason why the results of preclinical in vitro studies hardly match up with outcomes of vitamin D-related clinical studies. Regarding future studies addressing these concerns, we suggest establishing reference ranges of tissue-specific vitamin D metabolites within various cancer entities, carrying out model studies on human cancer cells and patient-derived organoids with biologically relevant calcitriol concentrations, and lastly improving the design of vitamin D clinical trials where results from preclinical studies guide the protocols and endpoints within these trials.
Topics: Prostatic Neoplasms; Humans; Male; Vitamin D; Calcitriol; Animals
PubMed: 38791324
DOI: 10.3390/ijms25105286 -
International Journal of Molecular... May 2024Sympathetic nervous system (SNS) hyperactivity is mediated by elevated catecholamine (CA) secretion from the adrenal medulla, as well as enhanced norepinephrine (NE)...
Sympathetic nervous system (SNS) hyperactivity is mediated by elevated catecholamine (CA) secretion from the adrenal medulla, as well as enhanced norepinephrine (NE) release from peripheral sympathetic nerve terminals. Adrenal CA production from chromaffin cells is tightly regulated by sympatho-inhibitory α-adrenergic (auto)receptors (ARs), which inhibit both epinephrine (Epi) and NE secretion via coupling to Gi/o proteins. α-AR function is, in turn, regulated by G protein-coupled receptor (GPCR)-kinases (GRKs), especially GRK2, which phosphorylate and desensitize them, i.e., uncouple them from G proteins. On the other hand, the short-chain free fatty acid (SCFA) receptor (FFAR)-3, also known as GPR41, promotes NE release from sympathetic neurons via the Gi/o-derived free Gβγ-activated phospholipase C (PLC)-β/Ca signaling pathway. However, whether it exerts a similar effect in adrenal chromaffin cells is not known at present. In the present study, we examined the interplay of the sympatho-inhibitory α-AR and the sympatho-stimulatory FFAR3 in the regulation of CA secretion from rat adrenal chromaffin (pheochromocytoma) PC12 cells. We show that FFAR3 promotes CA secretion, similarly to what GRK2-dependent α-AR desensitization does. In addition, FFAR3 activation enhances the effect of the physiologic stimulus (acetylcholine) on CA secretion. Importantly, GRK2 blockade to restore α-AR function or the ketone body beta-hydroxybutyrate (BHB or 3-hydroxybutyrate), via FFAR3 antagonism, partially suppress CA production, when applied individually. When combined, however, CA secretion from PC12 cells is profoundly suppressed. Finally, propionate-activated FFAR3 induces leptin and adiponectin secretion from PC12 cells, two important adipokines known to be involved in tissue inflammation, and this effect of FFAR3 is fully blocked by the ketone BHB. In conclusion, SCFAs can promote CA and adipokine secretion from adrenal chromaffin cells via FFAR3 activation, but the metabolite/ketone body BHB can effectively inhibit this action.
Topics: Animals; PC12 Cells; Rats; Receptors, G-Protein-Coupled; Catecholamines; Receptors, Adrenergic, alpha-2; Adipokines; Chromaffin Cells; Signal Transduction; Norepinephrine
PubMed: 38791266
DOI: 10.3390/ijms25105227 -
Archives of Endocrinology and Metabolism May 2024Burosumab, a monoclonal antibody directed against the fibroblast growth factor 23 (FGF23), has been approved for the treatment of X-linked hypophosphatemia (XLH). We... (Comparative Study)
Comparative Study
Burosumab, a monoclonal antibody directed against the fibroblast growth factor 23 (FGF23), has been approved for the treatment of X-linked hypophosphatemia (XLH). We conducted a systematic review to compare the efficacy and safety of burosumab versus conventional therapy (phosphorus and calcitriol) on XLH treatment. After a comprehensive literature search on MEDLINE/PubMed and Embase, we found nine studies for inclusion in the analysis. Risk of bias was assessed, and a random-effects model was used to determine the effect size. Clinical, biochemical, and radiological parameters of disease severity before and after treatment were analyzed and expressed in standardized mean difference (SMD). Burosumab resulted in normalization of phosphate homeostasis with an increase in renal tubular phosphate reabsorption and significant resolution of skeletal lesions (change in Thacher's total rickets severity score SMD: -1.46, 95% confidence interval [CI]: -1.76 to -1.17, < 0.001, improvement in deformities, and decline in serum alkaline phosphatase levels [SMD: 130.68, 95% CI: 125.26-136.1, < 0.001)]. Conventional therapy led to similar improvements in all these parameters but to a lower degree. In adults, burosumab normalized phosphorus levels (SMD: 1.23, 95% CI: 0.98-1.47, < 0.001) with resultant clinical improvement. Burosumab treatment was well tolerated, with only mild treatment-related adverse effects. The present review indicates a potential role for burosumab in improving rickets, deformities, and growth in children with XLH. Given its superior efficacy and safety profile, burosumab could be an effective therapeutic option in children. We suggest further studies comparing burosumab versus conventional therapy in children and adults with XLH.
Topics: Humans; Familial Hypophosphatemic Rickets; Antibodies, Monoclonal, Humanized; Fibroblast Growth Factor-23; Treatment Outcome; Calcitriol; Antibodies, Monoclonal; Phosphorus
PubMed: 38788147
DOI: 10.20945/2359-4292-2023-0242 -
American Journal of Physiology. Heart... Jul 2024Perivascular adipose tissue (PVAT) regulates vascular tone by releasing anticontractile factors. These anticontractile factors are driven by processes downstream of...
Perivascular adipose tissue (PVAT) regulates vascular tone by releasing anticontractile factors. These anticontractile factors are driven by processes downstream of adipocyte stimulation by norepinephrine; however, whether norepinephrine originates from neural innervation or other sources is unknown. The goal of this study was to test the hypothesis that neurons innervating PVAT provide the adrenergic drive to stimulate adipocytes in aortic and mesenteric perivascular adipose tissue (aPVAT and mPVAT), and white adipose tissue (WAT). Healthy male and female mice (8-13 wk) were used in all experiments. Expression of genes associated with synaptic transmission were quantified by qPCR and adipocyte activity in response to neurotransmitters and neuron depolarization was assessed in mice. Immunostaining, tissue clearing, and transgenic reporter lines were used to assess anatomical relationships between nerves and adipocytes. Although synaptic transmission component genes are expressed in adipose tissues (aPVAT, mPVAT, and WAT), strong nerve stimulation with electrical field stimulation does not significantly trigger calcium responses in adipocytes. However, norepinephrine consistently elicits strong calcium responses in adipocytes from all adipose tissues studied. Bethanechol induces minimal adipocyte responses. Imaging neural innervation using various techniques reveals that nerve fibers primarily run alongside blood vessels and rarely branch into the adipose tissue. Although nerve fibers are associated with blood vessels in adipose tissue, they demonstrate limited anatomical and functional interactions with adjacent adipocytes, challenging the concept of classical innervation. These findings dispute the significant involvement of neural input in regulating PVAT adipocyte function and emphasize alternative mechanisms governing adrenergic-driven anticontractile functions of PVAT. This study challenges prevailing views on neural innervation in perivascular adipose tissue (PVAT) and its role in adrenergic-driven anticontractile effects on vasculature. Contrary to existing paradigms, limited anatomical and functional connections were found between PVAT nerve fibers and adipocytes, underscoring the importance of exploring alternative mechanistic pathways. Understanding the mechanisms involved in PVAT's anticontractile effects is critical for developing potential therapeutic interventions against dysregulated vascular tone, hypertension, and cardiovascular disease.
Topics: Animals; Male; Female; Adipocytes; Norepinephrine; Mice; Adipose Tissue; Mice, Inbred C57BL; Synaptic Transmission; Adipose Tissue, White; Mice, Transgenic; Calcium Signaling
PubMed: 38787382
DOI: 10.1152/ajpheart.00041.2024 -
Cells May 2024Heart failure is the common concluding pathway for a majority of cardiovascular diseases and is associated with cardiac dysfunction. Since heart failure is invariably... (Review)
Review
Heart failure is the common concluding pathway for a majority of cardiovascular diseases and is associated with cardiac dysfunction. Since heart failure is invariably preceded by adaptive or maladaptive cardiac hypertrophy, several biochemical mechanisms have been proposed to explain the development of cardiac hypertrophy and progression to heart failure. One of these includes the activation of different neuroendocrine systems for elevating the circulating levels of different vasoactive hormones such as catecholamines, angiotensin II, vasopressin, serotonin and endothelins. All these hormones are released in the circulation and stimulate different signal transduction systems by acting on their respective receptors on the cell membrane to promote protein synthesis in cardiomyocytes and induce cardiac hypertrophy. The elevated levels of these vasoactive hormones induce hemodynamic overload, increase ventricular wall tension, increase protein synthesis and the occurrence of cardiac remodeling. In addition, there occurs an increase in proinflammatory cytokines and collagen synthesis for the induction of myocardial fibrosis and the transition of adaptive to maladaptive hypertrophy. The prolonged exposure of the hypertrophied heart to these vasoactive hormones has been reported to result in the oxidation of catecholamines and serotonin via monoamine oxidase as well as the activation of NADPH oxidase via angiotensin II and endothelins to promote oxidative stress. The development of oxidative stress produces subcellular defects, Ca-handling abnormalities, mitochondrial Ca-overload and cardiac dysfunction by activating different proteases and depressing cardiac gene expression, in addition to destabilizing the extracellular matrix upon activating some metalloproteinases. These observations support the view that elevated levels of various vasoactive hormones, by producing hemodynamic overload and activating their respective receptor-mediated signal transduction mechanisms, induce cardiac hypertrophy. Furthermore, the occurrence of oxidative stress due to the prolonged exposure of the hypertrophied heart to these hormones plays a critical role in the progression of heart failure.
Topics: Heart Failure; Humans; Cardiomegaly; Signal Transduction; Animals; Angiotensin II; Oxidative Stress
PubMed: 38786079
DOI: 10.3390/cells13100856 -
Biomolecules May 2024The active vitamin D metabolites, 25-hydroxyvitamin D (25D) and 1,25-dihydroxyvitamin D (1,25D), are produced by successive hydroxylation steps and play key roles in...
The active vitamin D metabolites, 25-hydroxyvitamin D (25D) and 1,25-dihydroxyvitamin D (1,25D), are produced by successive hydroxylation steps and play key roles in several cellular processes. However, alternative metabolic pathways exist, and among them, the 4-hydroxylation of 25D is a major one. This study aims to investigate the structure-activity relationships of 4-hydroxy derivatives of 1,25D. Structural analysis indicates that 1,4α,25(OH)D and 1,4β,25(OH)D maintain the anchoring hydrogen bonds of 1,25D and form additional interactions, stabilizing the active conformation of VDR. In addition, 1,4α,25D and 1,4β,25D are as potent as 1,25D in regulating the expression of VDR target genes in rat intestinal epithelial cells and in the mouse kidney. Moreover, these two 4-hydroxy derivatives promote hypercalcemia in mice at a dose similar to that of the parent compound.
Topics: Animals; Mice; Structure-Activity Relationship; Receptors, Calcitriol; Rats; Calcitriol; Male; Vitamin D; Hypercalcemia; Kidney
PubMed: 38785958
DOI: 10.3390/biom14050551 -
Renal Failure Dec 2024Renal fibrosis contributes to chronic renal failure and a decline in the quality of life. Bushen Huoxue (BSHX) formula is a Traditional Chinese Medicine used to treat...
BACKGROUND
Renal fibrosis contributes to chronic renal failure and a decline in the quality of life. Bushen Huoxue (BSHX) formula is a Traditional Chinese Medicine used to treat chronic renal failure. However, its mechanisms of action remain unclear.
METHODS AND RESULTS
In this study, a rat model of renal fibrosis was constructed by 5/6 nephrectomy , and histopathological changes were analyzed using hematoxylin-eosin and Masson's trichrome staining. Angiotensin II (Ang II) was used to establish an renal fibrosis cell model . Pyroptosis was measured using flow cytometry. Related markers of fibrosis and NOD-like receptor protein 3 (NLRP3) inflammasome activation were measured using western blotting and enzyme-linked immunosorbent assay. Treatment with BSHX (0.25, 0.5, and 1 g/kg) significantly inhibited renal fibrosis and damage in 5/6 nephrectomized rats and simultaneously reduced oxidative stress and NLRP3 inflammasome activation. Similarly, BSHX treatment reduced the levels of hydroxyproline, transforming growth factor-β, matrix metalloproteinase 2, and matrix metalloproteinase 9 and inactivated the Smad2/3 signaling pathway in Ang II-treated HK-2 cells. Our data also showed that treatment with BSHX reduced NLRP3 inflammasome activation and pyroptosis in Ang II-treated HK-2 cells. Moreover, fibrosis and pyroptosis in HK-2 cells induced by NLRP3 overexpression were reduced by treatment with BSHX.
CONCLUSIONS
BSHX significantly reduced renal fibrosis and pyroptosis, and its mechanism was mainly associated with the inhibition of reactive oxygen species (ROS)/NLRP3-mediated inflammasome activation.
Topics: Animals; NLR Family, Pyrin Domain-Containing 3 Protein; Pyroptosis; Rats; Drugs, Chinese Herbal; Fibrosis; Inflammasomes; Reactive Oxygen Species; Male; Renal Insufficiency, Chronic; Disease Models, Animal; Rats, Sprague-Dawley; Oxidative Stress; Humans; Kidney; Signal Transduction; Cell Line; Angiotensin II; Nephrectomy
PubMed: 38785272
DOI: 10.1080/0886022X.2024.2354444 -
Journal of Cellular and Molecular... May 2024Heart failure is a leading cause of death in the elderly. Traditional Chinese medicine, a verified alternative therapeutic regimen, has been used to treat heart failure,...
Heart failure is a leading cause of death in the elderly. Traditional Chinese medicine, a verified alternative therapeutic regimen, has been used to treat heart failure, which is less expensive and has fewer adverse effects. In this study, a total of 15 active ingredients of Astragalus membranaceus (Huangqi, HQ) were obtained; among them, Isorhamnetin, Quercetin, Calycosin, Formononetin, and Kaempferol were found to be linked to heart failure. Ang II significantly enlarged the cell size of cardiomyocytes, which could be partially reduced by Quercetin, Isorhamnetin, Calycosin, Kaempferol, or Formononetin. Ang II significantly up-regulated ANP, BNP, β-MHC, and CTGF expressions, whereas Quercetin, Isorhamnetin, Calycosin, Kaempferol or Formononetin treatment partially downregulated ANP, BNP, β-MHC and CTGF expressions. Five active ingredients of HQ attenuated inflammation in Ang II-induced cardiomyocytes by inhibiting the levels of TNF-α, IL-1β, IL-18 and IL-6. Molecular docking shows Isorhamnetin, Quercetin, Calycosin, Formononetin and Kaempferol can bind with its target protein ESR1 in a good bond by intermolecular force. Quercetin, Calycosin, Kaempferol or Formononetin treatment promoted the expression levels of ESR1 and phosphorylated ESR1 in Ang II-stimulated cardiomyocytes; however, Isorhamnetin treatment had no effect on ESR1 and phosphorylated ESR1 expression levels. In conclusion, our results comprehensively illustrated the bioactives, potential targets, and molecular mechanism of HQ against heart failure. Isorhamnetin, Quercetin, Calycosin, Formononetin and Kaempferol might be the primary active ingredients of HQ, dominating its cardioprotective effects against heart failure through regulating ESR1 expression, which provided a basis for the clinical application of HQ to regulate cardiac hypertrophy and heart failure.
Topics: Astragalus propinquus; Heart Failure; Molecular Docking Simulation; Myocytes, Cardiac; Animals; Drugs, Chinese Herbal; Network Pharmacology; Quercetin; Angiotensin II; Kaempferols; Rats; Humans; Isoflavones
PubMed: 38780500
DOI: 10.1111/jcmm.18331 -
Scientific Reports May 2024We studied the inhibitory actions of docosahexaenoic acid (DHA) on the contractions induced by carbachol (CCh), angiotensin II (Ang II), and bradykinin (BK) in guinea...
We studied the inhibitory actions of docosahexaenoic acid (DHA) on the contractions induced by carbachol (CCh), angiotensin II (Ang II), and bradykinin (BK) in guinea pig (GP) gastric fundus smooth muscle (GFSM), particularly focusing on the possible inhibition of store-operated Ca channels (SOCCs). DHA significantly suppressed the contractions induced by CCh, Ang II, and BK; the inhibition of BK-induced contractions was the strongest. Although all contractions were greatly dependent on external Ca, more than 80% of BK-induced contractions remained even in the presence of verapamil, a voltage-dependent Ca channel inhibitor. BK-induced contractions in the presence of verapamil were not suppressed by LOE-908 (a receptor-operated Ca channel (ROCC) inhibitor) but were suppressed by SKF-96365 (an SOCC and ROCC inhibitor). BK-induced contractions in the presence of verapamil plus LOE-908 were strongly inhibited by DHA. Furthermore, DHA inhibited GFSM contractions induced by cyclopiazonic acid (CPA) in the presence of verapamil plus LOE-908 and inhibited the intracellular Ca increase due to Ca addition in CPA-treated 293T cells. These findings indicate that Ca influx through SOCCs plays a crucial role in BK-induced contraction in GP GFSM and that this inhibition by DHA is a new mechanism by which this fatty acid inhibits GFSM contractions.
Topics: Animals; Guinea Pigs; Docosahexaenoic Acids; Bradykinin; Muscle, Smooth; Carbachol; Muscle Contraction; Angiotensin II; Gastric Fundus; Verapamil; Calcium; Male; Humans; Calcium Channels; HEK293 Cells; Calcium Channel Blockers; Imidazoles
PubMed: 38778154
DOI: 10.1038/s41598-024-62578-y