Anti-inflammatory activity of palmitoylethanolamide ameliorates osteoarthritis induced by monosodium iodoacetate in Sprague-Dawley rats.

Novel treatment strategies are urgently required for osteoarthritis (OA). Palmitoylethanolamide (PEA) is a naturally occurring fatty acid amide with analgesic and anti-inflammatory effects. We aimed to examine its effect on OA and elucidate the molecular mechanism of actions in monosodium iodoacetate (MIA)-induced OA Sprague-Dawley rats. The experimental animals were divided into normal control group (injected with saline + treated with phosphate-buffered saline (PBS), NOR), control group (injected with MIA + treated with PBS, CON), 50 or 100 mg/kg body weight (BW)/day PEA-treated group (injected with MIA + treated with 50 or 100 mg of PEA/kg BW/day, PEA50 or PEA100), and positive control group (injected with MIA + treated with 6 mg of diclofenac/kg BW/day, DiC). The changes in blood parameters, body parameters, gene expression of inflammatory mediators and cytokines, knee thickness, and joint tissue were observed. Oral administration of PEA had no adverse effects on the BW, liver, or kidneys. PEA reduced knee joint swelling and cartilage degradation in MIA-induced OA rats. The serum levels of leukotriene B4, nitric oxide, tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and prostaglandin E2 considerably reduced in the PEA100 group compared with those in the CON group. In the synovia of knee joints, the mRNA expression of iNOS, 5-Lox, Cox-2, Il-1ß, Tnf-α, and Mmp-2, -3, -9, and -13 apparently increased with MIA administration. Meanwhile, Timp-1 mRNA expression apparently decreased in the CON group but increased to the normal level with PEA treatment. Thus, PEA can be an effective therapeutic agent for OA.

Change in alkaline phosphatase activity associated with intensive care unit and hospital length of stay in patients with septic acute kidney injury on continuous renal replacement therapy.

BACKGROUND: Evidence suggests that alkaline phosphatase attenuates inflammatory response in sepsis by lipopolysaccharide detoxification and adenosine triphosphate dephosphorylation. We sought to determine changes in alkaline phosphatase (AP) activity during septic acute kidney injury (AKI) and clinical parameters associated with AP activity. METHODS: In this retrospective study, we investigated baseline (when initiating CRRT) and follow-up AP activity on day 3, and associated outcomes in patients who underwent continuous renal replacement therapy (CRRT) due to septic AKI. RESULTS: We analyzed the baseline AP activity of 155 patients and day 3 AP activity in 123 patients. Baseline AP activity was not associated with renal or inflammatory biomarkers, or outcomes. It did not significantly differ between the 75 survivors and 80 non-survivors (p = 0.155). AP activity was higher on day 3 than at baseline (105 U/L [interquartile range, 79-156] vs 90 U/L [interquartile range, 59-133]). In particular, liver and bone isoforms increased significantly (p < 0.05), but intestine isoforms did not reach statistical significance (p = 0.367). In addition, day 3 AP activity showed a weak correlation with length of ICU stay (r = 0.213, p = 0.018) and length of hospital stay (r = 0.216, p = 0.017), but not with survival (r = - 0.035, p = 0.698). CONCLUSION: Endogenous AP activity significantly increased in patients with septic AKI. However, neither baseline nor follow-up AP activity was associated with survival.

Enhanced Systemic Anti-Angiogenic siVEGF Delivery Using PEGylated Oligo-d-arginine.

Angiogenesis mainly mediated by upregulation of vascular endothelial growth factor (VEGF) provides a hallmark of rapidly proliferating tumor cells and an essential component of the tumor growth and microenvironment, making it a targetable process for antitumor therapy. RNA interference (RNAi) provides a very effective tool for developing antitumor therapies; however, its application to date has been hampered due to the lack of efficient small interfering RNA (siRNA) delivery systems in vivo. Here, we report a polymeric gene carrier system based on PEGylation of a cationic cysteine-ended 9-mer arginine oligopeptide (CR9C), which provides effective siRNA systemic delivery and specifically suppresses VEGF (siVEGF). The PEG500-CR9C/siVEGF oligopeptoplex provided improved blood circulation, enhanced protection from serum proteases, reduced uptake in the liver and kidneys, enhanced tumor targeting, and down-regulated intratumoral VEGF level, which comprehensively resulted in improved antitumor efficacy without significant toxicity in vivo. PEG500-CR9C has a great potential for safe and efficient siRNA delivery with diverse applications.

Tat-antioxidant 1 protects against stress-induced hippocampal HT-22 cells death and attenuate ischaemic insult in animal model.

Oxidative stress-induced reactive oxygen species (ROS) are responsible for various neuronal diseases. Antioxidant 1 (Atox1) regulates copper homoeostasis and promotes cellular antioxidant defence against toxins generated by ROS. The roles of Atox1 protein in ischaemia, however, remain unclear. In this study, we generated a protein transduction domain fused Tat-Atox1 and examined the roles of Tat-Atox1 in oxidative stress-induced hippocampal HT-22 cell death and an ischaemic injury animal model. Tat-Atox1 effectively transduced into HT-22 cells and it protected cells against the effects of hydrogen peroxide (H2O2)-induced toxicity including increasing of ROS levels and DNA fragmentation. At the same time, Tat-Atox1 regulated cellular survival signalling such as p53, Bad/Bcl-2, Akt and mitogen-activate protein kinases (MAPKs). In the animal ischaemia model, transduced Tat-Atox1 protected against neuronal cell death in the hippocampal CA1 region. In addition, Tat-Atox1 significantly decreased the activation of astrocytes and microglia as well as lipid peroxidation in the CA1 region after ischaemic insult. Taken together, these results indicate that transduced Tat-Atox1 protects against oxidative stress-induced HT-22 cell death and against neuronal damage in animal ischaemia model. Therefore, we suggest that Tat-Atox1 has potential as a therapeutic agent for the treatment of oxidative stress-induced ischaemic damage.

PEP-1-PEA-15 protects against toxin-induced neuronal damage in a mouse model of Parkinson's disease.

BACKGROUND: PEA-15 is abundantly expressed in both neurons and astrocytes throughout the brain. It is a multifunctional protein with the ability to increase cell survival via anti-apoptotic and anti-proliferative properties. However, the function of PEA-15 in neuronal diseases such as Parkinson's disease (PD) remains unclear. In this study, we investigated the protective effects of PEA-15 on neuronal damage induced by MPP(+) in neuroblastoma SH-SY5Y and BV2 microglia cells and in a MPTP-induced PD mouse model using cell-permeable PEP-1-PEA-15. METHODS: PEP-1-PEA-15 was purified using affinity chromatography. Cell viability and DNA fragmentation were examined by MTT assay and TUNEL staining. Dopaminergic neuronal cell death in the animal model was examined by immunohistochemistry. RESULTS: PEP-1-PEA-15 transduced into the SH-SY5Y and BV2 cells in a time- and dose-dependent manner. Transduced PEP-1-PEA-15 protected against MPP(+)-induced toxicity by inhibiting intracellular ROS levels and DNA fragmentation. Further, it enhanced the expression levels of Bcl-2 and caspase-3 while reducing the expression levels of Bax and cleaved caspase-3. We found that PEP-1-PEA-15 transduced into the substantia nigra and prevented dopaminergic neuronal cell death in a MPTP-induced PD mouse. Also, we showed the neuroprotective effects in the model by demonstrating that treatment with PEP-1-PEA-15 ameliorated MPTP-induced behavioral dysfunctions and increased dopamine levels in the striatum. CONCLUSIONS: PEP-1-PEA-15 can efficiently transduce into cells and protects against neurotoxin-induced neuronal cell death in vitro and in vivo. GENERAL SIGNIFICANCE: These results demonstrate the potential for PEP-1-PEA-15 to provide a new strategy for protein therapy treatment of a variety of neurodegenerative diseases including PD.

Rhus verniciflua extract modulates survival of MCF-7 breast cancer cells through the modulation of AMPK-pathway.

Rhus verniciflua STOKES (RVS) is used as an anti-cancer agent in traditional herbal medicine. However, the underlying molecular mechanism of its action is poorly understood. Here, we elucidated the mechanism of the anti-cancer mechanism of RVS in MCF-7 human breast cancer cells. We found that RVS increased the phosphorylation of AMP-activated protein kinase (AMPK) and downstream acetyl-CoA carboxylase (ACC) and suppressed cell viability in an AMPK-dependent fashion. RVS also induced an increase in reactive oxygen species (ROS) levels. RVS-induced AMPK phosphorylation was not observed in the presence of N-acetyl-cysteine (NAC), which indicated that ROS is associated with RVS-induced AMPK phosphorylation. In addition, fluorescent staining (Annexin V/propidium iodide) revealed that RVS increased the expression of Annexin V, which indicates that RVS leads to cancer-induced apoptosis. Moreover, RVS increased the phosphorylation of p53 and the expression of Bax. The inhibition of AMPK blocked RVS-induced p53 phosphorylation and Bax expression, which suggests that AMPK is involved in RVS-induced cancer apoptosis. Taken together, these results demonstrate that RVS has anti-tumor effects on MCF-7 cells through an AMPK-signaling pathway.

Effect of taurine chloramine on differentiation of human preadipocytes into adipocytes.

We investigated whether taurine chloramine (TauCl), which is -endogenously produced by immune cells such as macrophages that infiltrate adipose tissue, affects the differentiation of preadipocytes into adipocytes or modulates the expression of adipokines in adipocytes. To study the physiological effects of TauCl on human adipocyte differentiation and adipokine expression, preadipocytes were cultured under differentiation conditions for 14 days in the presence or the absence of TauCl. Differentiated adipocytes were also treated with TauCl in the presence or the absence of IL-1ß (1 ng/ml) for 7 days. The culture supernatants were analyzed for adipokines such as adiponectin, leptin, IL-6, and IL-8. At concentrations of 400-600 µM, TauCl significantly inhibited the differentiation of human preadipocytes into adipocytes in a dose-dependent manner. It did not induce the dedifferentiation of adipocytes or inhibit fat accumulation in adipocytes. Expression of major transcription factors of adipogenesis and adipocyte marker genes was decreased after treatment with TauCl, in agreement with its inhibition of -differentiation. These results suggest that TauCl may inhibit the differentiation of -preadipocytes into adipocytes. Thus, TauCl or more stable derivatives of TauCl could potentially be a safe drug therapy for obesity-related diseases.

A case of myotonic dystrophy with electrolyte imbalance.

Type 1 myotonic dystrophy (DM1) is an autosomal-dominant inherited disorder with a multisystem involvement, caused by an abnormal expansion of the CTG sequence of the dystrophic myotonia protein kinase (DMPK) gene. DM1 is a variable multisystem disorder with muscular and nonmuscular abnormalities. Increasingly, endocrine abnormalities, such as gonadal, pancreatic, and adrenal dysfunction are being reported. But, Electrolytes imbalance is a very rare condition in patients with DM1 yet. Herein we present a 42-yr-old Korean male of DM1 with abnormally elevated serum sodium and potassium. The patient had minimum volume of maximally concentrated urine without water loss. It was only cured by normal saline hydration. The cause of hypernatremia was considered by primary hypodipsia. Hyperkalemic conditions such as renal failure, pseudohyperkalemia, cortisol deficiency and hyperkalemic periodic paralysis were excluded. Further endocrine evaluation suggested selective hyperreninemic hypoaldosteronism as a cause of hyperkalemia.

Cystatin C as a Predictor of Renal Function and Methotrexate-Associated Toxicities in Patients With Rheumatoid Arthritis.

OBJECTIVE: Methotrexate (MTX) is an anchor drug for most patients with rheumatoid arthritis (RA); however, its use may be limited depending on renal function. Therefore, this study aimed to examine the discrepancy in the estimated glomerular filtration rate (eGFR) using conventional serum creatinine (SCr)-, cystatin C-, and MTX-associated toxicities in patients with RA. METHODS: In total, 436 patients were enrolled, and eGFR was evaluated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation based on both cystatin C and SCr levels. The CKD and MTX dosing stages were classified according to eGFR. MTX-associated toxicities were also evaluated. RESULTS: The mean eGFR using CKD-EPI cystatin C (CKD-EPIcys) was 89.44 mL/min/1.73 m2, lower than the eGFR using CKD-EPI SCr (CKD-EPISCr) of 95.55 mL/min/1.73 m2. After converting eGFR to CKD-EPIcys by CKD-EPISCr, 29.8% of patients were reclassified to a higher stage according to the Kidney Disease: Improving Global Outcomes CKD stage. Also, according to the MTX guidelines, 6.4% of the group with an eGFR > 50 mL/min/1.73 m2 were reclassified to eGFR 10-50 mL/1.73 m2, requiring dose adjustment. The incidence of MTX-associated toxicities, such as anemia, leukopenia, and nephrotoxicity, was significantly higher in the CKD stage-changed group than in the nonstage-changed group. CONCLUSION: Our results showed that eGFR based on SCr was overestimated compared with eGFR based on cystatin C. In addition, we demonstrated that MTX-associated toxicities were significantly increased in the group with a changed stage when the eGFR was converted from CKD-EPISCr to CKD-EPIcys.

Immune-enhancing effect of hydrolyzed and fermented Platycodon grandiflorum extract in cyclophosphamide-induced immunosuppressed BALB/c mice.

BACKGROUND/OBJECTIVES: The immunomodulatory effect of Platycodon grandiflorum (PG) has been reported, but studies on its mechanism are still lacking. This study was undertaken to confirm whether the hydrolyzed and fermented PG extract (HFPGE) obtained by adding hydrolysis and fermentation to the extraction process has an immune-enhancing effect in the in vivo system. MATERIALS/METHODS: Five-week-old BALB/c mice were divided into 4 groups: normal control group (NOR), control group (CON), 150 mg/kg body weight (BW)/day HFPGE-treated group (T150), and 300 mg/kg BW/day HFPGE-treated group (T300). The mice were administered HFPGE for 4 weeks and intraperitoneally injected with cyclophosphamide (CPA, 80 mg/kg BW/day) on day 6, 7, and 8, respectively, to induce immunosuppression. The levels of immunoglobulins (Igs) and cytokines were measured in the serum. In splenocytes, proliferation and cytokine levels were measured. RESULTS: Serum IgA, IgG, and IgM levels were observed to decrease after CPA treatment, which was recovered by HFPGE administration. The levels of serum interleukin (IL)-12, tumor necrosis factor (TNF)-α, IL-8, and transforming growth factor (TGF)-ß were also decreased after exposure to CPA but increased after HFPGE administration. Decreased splenocyte proliferation was seen in CPA-treated mice, but was observed to increase in the T150 and T300 groups as compared to the NOR group. Compared to the CON group, splenocyte proliferation stimulated with concanavalin A (ConA) or lipopolysaccharide (LPS) in the HFPGE-treated groups was significantly increased. The cytokines secreted by ConA-stimulated splenocytes (IL-2, IL-12, interferon-γ, TNF-α) were increased in the T150 and T300 groups, and cytokines secreted by LPS-stimulated splenocytes (IL-4, IL-8, TGF-ß) were also increased by HFPGE administration. CONCLUSION: These results suggest that HFPGE stimulates the immunity in immunosuppressed conditions, thereby enhancing the immune response. Therefore, it is expected that HFPGE has the potential to be used as functional food and medicine for immune recovery in various immunocompromised situations.

Agaricus bisporus Extract Exerts an Anti-Obesity Effect in High-Fat Diet-Induced Obese C57BL/6N Mice by Inhibiting Pancreatic Lipase-Mediated Fat Absorption.

Agaricus bisporus is well known as a source of polysaccharides that could improve human health. The objective of this study was to explore the anti-obesity effect of A. bisporus extract (ABE), abundant in polysaccharides, and its underlying mechanism. Pancreatic lipase inhibitory activity in vitro was determined after treatment with ABE and chitosan. Treatment with ABE and chitosan significantly decreased pancreatic lipase activity. Five-week-old male SD rats were randomly divided into three groups for acute feeding with vehicle, ABE at 80 mg/kg body weight (BW)/day, and ABE at 160 mg/kg BW/day. ABE dose-dependently increased plasma lipid clearance in an oral lipid tolerance test. Five-week-old male C57BL/6N mice were fed a control diet (CD), a high-fat diet (HFD), an HFD with ABE at 80 mg/kg BW/day, ABE at 160 mg/kg BW/day, or chitosan at 160 mg/kg BW/day for eight weeks. HFD-fed mice showed significant increases in body weight, fat mass, white adipose tissue, average lipid droplet size, and serum levels of glucose, triglyceride, ALT, and AST compared to those in the CD group. However, ABE or chitosan administration ameliorated these increases. ABE or chitosan significantly reduced dietary efficiency and increased fecal excretion levels of lipids, triglycerides, and total cholesterol. These in vitro and in vivo findings suggest that ABE might act as an anti-obesity agent by inhibiting pancreatic lipase-mediated lipid absorption, at least in part.

Anti-inflammatory effects of Tat-Annexin protein on ovalbumin-induced airway inflammation in a mouse model of asthma.

Chronic airway inflammation is a key feature of bronchial asthma. Annexin-1 (ANX1) is an anti-inflammatory protein that is an important modulator and plays a key role in inflammation. Although the precise action of ANX1 remains unclear, it has emerged as a potential drug target for inflammatory diseases such as asthma. To examine the protective effects of ANX1 protein on ovalbumin (OVA)-induced asthma in animal models, we used a cell-permeable Tat-ANX1 protein. Mice sensitized and challenged with OVA antigen had an increased amount of cytokines and eosinophils in their bronchoalveolar lavage (BAL) fluid. However, administration of Tat-ANX1 protein before OVA challenge significantly decreased the levels of cytokines (interleukin (IL)-4, IL-5, and IL-13) and BAL fluid in lung tissues. Furthermore, OVA significantly increased the activation of mitogen-activated protein kinase (MAPK) in lung tissues, whereas Tat-ANX1 protein markedly reduced phosphorylation of MAPKs such as extracellular signal-regulated protein kinase, p38, and stress-activated protein kinase/c-Jun N-terminal kinase. These results suggest that transduced Tat-ANX1 protein may be a potential protein therapeutic agent for the treatment of lung disorders including asthma.

Does stage III chronic kidney disease always progress to end-stage renal disease? A ten-year follow-up study.

OBJECTIVE: Clinically, it may be appropriate to subdivide patients with stage 3 chronic kidney disease (CKD) into two subgroups, as they show different risks for kidney outcomes. This study evaluated the proportion of patients with stage 3 CKD who progressed to stage 4 or 5 CKD over 10 years and independent predictors of progression of renal dysfunction. It sought to validate whether stage 3 CKD patients should be subdivided. MATERIAL AND METHODS: This retrospective cohort study enrolled 347 stage 3 CKD patients between January 1997 and December 1999, who were followed up through June 2010. The baseline clinical characteristics and outcomes were compared in patients with stage 3A [45

The clinical significance of anti-cyclic citrullinated peptide antibody in primary Sjögren syndrome.

Anti-cyclic citrullinated peptide antibody (anti-CCP) is a specific marker for the diagnosis of rheumatoid arthritis. However, this antibody can be detected in other rheumatic diseases and even in healthy people. This study aims to determine the prevalence and the clinical significance of anti-CCP in patients with primary Sjögren syndrome (pSS). We analyzed the clinical and laboratory data of 95 patients with pSS by retrospective review of their medical records. Anti-CCP was measured by ELISA kit. Anti-CCP, rheumatoid factor (RF), anti-nuclear antibody, anti-Ro and anti-La antibodies, and clinical data were investigated. We analyzed clinical and serologic characteristics of anti-CCP-positive patients. Twenty-one patients (22.1%) had positive anti-CCP (mean titer 61.6 ± 15.6 U/ml) and 40 patients (42.1%) had positive RF (mean titer 98.8 ± 22.7 IU/ml). Seventy-nine patients (83.1%) had arthralgia, and 31 patients (32.6%) had non-erosive arthritis on physical examination and radiologic images. Anti-CCP-positive patients had more frequently positive RF (71.4% vs. 41.8%, P = 0.01) and anti-Ro antibody (85.7% vs. 60.8%, P = 0.03). Anti-CCP-positive patients had non-erosive arthritis more frequently than anti-CCP-negative patients (76.1% vs. 21.6%, P < 0.01). The prevalence of anti-CCP was 22.1% in pSS, and anti-CCP was associated with non-erosive arthritis, and positivity of RF and anti-Ro antibody.

Gynostemma pentaphyllum extract and its active component gypenoside L improve the exercise performance of treadmill-trained mice.

BACKGROUND/OBJECTIVES: The effectiveness of natural compounds in improving athletic ability has attracted attention in both sports and research. Gynostemma pentaphyllum (Thunb.) leaves are used to make traditional herbal medicines in Asia. The active components of G. pentaphyllum, dammarane saponins, or gypenosides, possess a range of biological activities. On the other hand, the anti-fatigue effects from G. pentaphyllum extract (GPE) and its effective compound, gypenoside L (GL), remain to be determined. MATERIALS/METHODS: This study examined the effects of GPE on fatigue and exercise performance in ICR mice. GPE was administered orally to mice for 6 weeks, with or without treadmill training. The biochemical analysis in serum, glycogen content, mRNA, and protein expressions of the liver and muscle were analyzed. RESULTS: The ExGPE (exercise with 300 mg/kg body weight/day of GPE) mice decreased the fat mass percentage significantly compared to the ExC mice, while the ExGPE showed the greatest lean mass percentage compared to the ExC group. The administration of GPE improved the exercise endurance and capacity in treadmill-trained mice, increased glucose and triglycerides, and decreased the serum creatine kinase and lactate levels after intensive exercise. The muscle glycogen levels were higher in the ExGPE group than the ExC group. GPE increased the level of mitochondrial biogenesis by enhancing the phosphorylation of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) protein and the mRNA expression of nuclear respiratory factor 1, mitochondrial DNA, peroxisome proliferator-activated receptor-δ, superoxide dismutase 2, and by decreasing the lactate dehydrogenase B level in the soleus muscle (SOL). GPE also improved PGC-1α activation in the SOL significantly through AMPK/p38 phosphorylation. CONCLUSIONS: These results showed that GPE supplementation enhances exercise performance and has anti-fatigue activity. In addition, the underlying molecular mechanism was elucidated. Therefore, GPE is a promising candidate for developing functional foods and enhancing the exercise capacity and anti-fatigue activity.

Immunostimulatory activity of hydrolyzed and fermented Platycodon grandiflorum extract occurs via the MAPK and NF-κB signaling pathway in RAW 264.7 cells.

BACKGROUND/OBJECTIVES: Platycodon grandiflorum (PG) has long been known as a medicinal herb effective in various diseases, including bronchitis and asthma, but is still more widely used for food. Fermentation methods are being applied to increase the pharmacological composition of PG extracts and commercialize them with high added value. This study examines the hydrolyzed and fermented PG extract (HFPGE) fermented with Lactobacillus casei in RAW 264.7 cells, and investigates the effect of amplifying the immune and the probable molecular mechanism. MATERIALS/METHODS: HFPGE's total phenolic, flavonoid, saponin, and platycodin D contents were analyzed by colorimetric analysis or high-performance liquid chromatography. Cell viability was measured by the MTT assay. Phagocytic activity was analyzed by a phagocytosis assay kit, nitric oxide (NO) production by a Griess reagent system, and cytokines by enzyme-linked immunosorbent assay kits. The mRNA expressions of inducible nitric oxide synthase (iNOS) and cytokines were analyzed by reverse transcription-polymerase chain reaction, whereas MAPK and nuclear factor (NF)-κB activation were analyzed by Western blots. RESULTS: Compared to PGE, HFPGE was determined to contain 13.76 times and 6.69 times higher contents of crude saponin and platycodin D, respectively. HFPGE promoted cell proliferation and phagocytosis in RAW 264.7 cells and regulated the NO production and iNOS expression. Treatment with HFPGE also resulted in increased production of interleukin (IL)-1ß, IL-6, tumor necrosis factor (TNF)-α, C-X-C motif chemokine ligand10, granulocyte-colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, and monocyte chemoattractant protein-1, and the mRNA expressions of these cytokines. HFPGE also resulted in significantly increasing the phosphorylation of NF-κB p65, extracellular signal-regulated kinase, and c-Jun N-terminal kinase. CONCLUSIONS: Taken together, our results imply that fermentation and hydrolysis result in the extraction of more active ingredients of PG. Furthermore, we determined that HFPGE exerts immunostimulatory activity via the MAPK and NF-κB signaling pathways.

Gynostemma pentaphyllum extract and Gypenoside L enhance skeletal muscle differentiation and mitochondrial metabolism by activating the PGC-1α pathway in C2C12 myotubes.

BACKGROUND/OBJECTIVES: Peroxisome proliferator-activated receptor-gamma co-activator-1α (PGC-1α) has a central role in regulating muscle differentiation and mitochondrial metabolism. PGC-1α stimulates muscle growth and muscle fiber remodeling, concomitantly regulating lactate and lipid metabolism and promoting oxidative metabolism. Gynostemma pentaphyllum (Thumb.) has been widely employed as a traditional herbal medicine and possesses antioxidant, anti-obesity, anti-inflammatory, hypolipemic, hypoglycemic, and anticancer properties. We investigated whether G. pentaphyllum extract (GPE) and its active compound, gypenoside L (GL), affect muscle differentiation and mitochondrial metabolism via activation of the PGC-1α pathway in murine C2C12 myoblast cells. MATERIALS/METHODS: C2C12 cells were treated with GPE and GL, and quantitative reverse transcription polymerase chain reaction and western blot were used to analyze the mRNA and protein expression levels. Myh1 was determined using immunocytochemistry. Mitochondrial reactive oxygen species generation was measured using the 2'7'-dichlorofluorescein diacetate assay. RESULTS: GPE and GL promoted the differentiation of myoblasts into myotubes and elevated mRNA and protein expression levels of Myh1 (type IIx). GPE and GL also significantly increased the mRNA expression levels of the PGC-1α gene (Ppargc1a), lactate metabolism-regulatory genes (Esrra and Mct1), adipocyte-browning gene fibronectin type III domain-containing 5 gene (Fndc5), glycogen synthase gene (Gys), and lipid metabolism gene carnitine palmitoyltransferase 1b gene (Cpt1b). Moreover, GPE and GL induced the phosphorylation of AMP-activated protein kinase, p38, sirtuin1, and deacetylated PGC-1α. We also observed that treatment with GPE and GL significantly stimulated the expression of genes associated with the anti-oxidative stress response, such as Ucp2, Ucp3, Nrf2, and Sod2. CONCLUSIONS: The results indicated that GPE and GL enhance exercise performance by promoting myotube differentiation and mitochondrial metabolism through the upregulation of PGC-1α in C2C12 skeletal muscle.

Effects of pergolide mesylate on transduction efficiency of PEP-1-catalase protein.

The low transduction efficiency of various proteins is an obstacle to their therapeutic application. However, protein transduction domains (PTDs) are well-known for a highly effective tool for exogenous protein delivery to cells. We examined the effects of pergolide mesylate (PM) on the transduction of PEP-1-catalase into HaCaT human keratinocytes and mice skin and on the anti-inflammatory activity of PEP-1-catatase against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation using Western blot and histological analysis. PM enhanced the time- and dose-dependent transduction of PEP-1-catalase into HaCaT cells without affecting the cellular toxicity. In a mouse edema model, PEP-1-catalase inhibited the increased expressions of inflammatory mediators and cytokines such as cyclooxygenase-2, inducible nitric oxide synthase, interleukin-6 and -1ß, and tumor necrosis factor-α induced by TPA. On the other hand, PM alone failed to exert any significant anti-inflammatory effects. However, the anti-inflammatory effect of co-treatment with PEP-1-catalase and PM was more potent than that of PEP-1-catalase alone. Our results indicate that PM may enhance the delivery of PTDs fusion therapeutic proteins to target cells and tissues and has potential to increase their therapeutic effects of such drugs against various diseases.

The clinical impact of gut microbiota in chronic kidney disease.

Gut microorganisms play critical roles in both maintaining host homeostasis and the development of diverse diseases. Gut dysbiosis, an alteration of the composition and function of gut microorganisms, is commonly seen in patients with chronic kidney disease (CKD). CKD itself contributes to a disruption of the symbiotic relationship between the gut microbiota and the host, while the resulting gut dysbiosis may play a part in stage progression of CKD. This bidirectional relationship supports the concept that the gut microbiota is considered a novel focus for the pathogenesis and management of CKD. This article examines the interaction between the gut microbiota and the kidney, the mutual effects of dysbiosis and CKD, and possible treatment options to restore gut eubiosis, and reduce CKD progression and its related complications.

Perception and attitudes of medical students on clinical clerkship in the era of the Coronavirus Disease 2019 pandemic.

BACKGROUND: The Coronavirus Disease 2019 (COVID-19) has been placing severe strain on global healthcare systems and medical education programs, leading to growing demands for medical students to assume the role of preliminary healthcare providers. OBJECTIVES: To assess the perception and attitudes of medical students about clinical clerkship training during the COVID-19 pandemic. DESIGN: A cross-sectional survey with web-based 3-fields/14-items questionnaire was conducted, from April 7 to 14, 2020, to evaluate their self-assessed perception and attitudes on clerkship training of hospital practice under the COVID-19 outbreak and spread among 161 (78 on pre-clerkship course, 83 on clinical clerkship course) medical students at Dankook University College of Medicine, Cheonan, Republic of Korea. RESULTS: Of the 151 medical students who completed the survey, 81 students (53.7%) considered themselves familiar with COVID-19. Although the students were concerned about the spread of the virus during clinical clerkship training, 118 (78.1%) students preferred the clerkship training in a hospital practice. The students in the clinical clerkship program preferred this over those in the pre-clerkship program (85.7% vs. 70.2%, P = 0.03), primarily because a clinical clerkship could not be replaced by an online class during the COVID-19 pandemic. In addition, their responses indicated, in order of significance, fear of not completing the clerkship course on time, willingness to participate as a preliminary healthcare provider in pandemic, the potential waste of tuition, and belief that a hospital is rather safe. The change in the academic calendar had not a positive impact on the lifestyles of many students. CONCLUSIONS: In circumstances such as the COVID-19 pandemic, educational strategies to clinical clerkship training for medical students should be developed to provide them with the opportunity to be actively involved in hospital practice under strict safety guidance focused on preventing virus infection and transmission.