Green Tea Polyphenol (-)-Epicatechin Pretreatment Mitigates Hepatic Steatosis in an In Vitro MASLD Model.

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is becoming more prominent globally due to an increase in the prevalence of obesity, dyslipidemia, and type 2 diabetes. A great deal of studies have proposed potential treatments for MASLD, with few of them demonstrating promising results. The aim of this study was to investigate the potential effects of (-)-epicatechin (EPI) on the development of MASLD in an in vitro model using the HepG2 cell line by determining the metabolic viability of the cells and the levels of PPARα, PPARγ, and GSH. HepG2 cells were pretreated with 10, 30, 50, and 100 µM EPI for 4 h to assess the potential effects of EPI on lipid metabolism. A MASLD cell culture model was established using HepG2 hepatocytes which were exposed to 1.5 mM oleic acid (OA) for 24 h. Moreover, colorimetric MTS assay was used in order to determine the metabolic viability of the cells, PPARα and PPARγ protein levels were determined using enzyme-linked immunosorbent assay (ELISA), and lipid accumulation was visualized using the Oil Red O Staining method. Also, the levels of intracellular glutathione (GSH) were measured to determine the level of oxidative stress. EPI was shown to increase the metabolic viability of the cells treated with OA. The metabolic viability of HepG2 cells, after 24 h incubation with OA, was significantly decreased, with a metabolic viability of 71%, compared to the cells pretreated with EPI, where the metabolic viability was 74-86% with respect to the concentration of EPI used in the experiment. Furthermore, the levels of PPARα, PPARγ, and GSH exhibited a decrease in response to increasing EPI concentrations. Pretreatment with EPI has demonstrated a great effect on the levels of PPARα, PPARγ, and GSH in vitro. Therefore, considering that EPI mediates lipid metabolism in MASLD, it should be considered a promising hepatoprotective agent in future research.

Implications of Dysnatremia and Endocrine Disturbances in COVID-19 Patients.

Sodium imbalance is a common electrolyte disturbance in COVID-19, often linked to disruptions in hormonal regulation. This review explores the relationship between sodium dysregulation and endocrine disturbances, particularly focusing on primary and secondary hypothyroidism, hypocortisolism, and the renin-angiotensin-aldosterone system (RAAS). Hypocortisolism in COVID-19, due to adrenal insufficiency or secondary to pituitary dysfunction, can lead to hyponatremia through inadequate cortisol levels, which impair renal free water excretion and enhance antidiuretic hormone (ADH) secretion. Similarly, hypothyroidism is associated with decreased renal blood flow and the glomerular filtration rate (GFR), which also increases ADH activity, leading to water retention and dilutional hyponatremia. Furthermore, COVID-19 can disrupt RAAS (primarily through its interaction with the angiotensin-converting enzyme 2 (ACE2) receptor), diminishing aldosterone secretion and further contributing to sodium loss and hyponatremia. These hormonal disruptions suggest that sodium imbalance in COVID-19 is multifactorial and warrants further investigation into the complex interplay between COVID-19, endocrine function, and sodium homeostasis. Future research should focus on understanding these mechanisms to develop management algorithms that address both sodium imbalance and underlying hormonal disturbances in order to improve prognosis and outcomes in COVID-19 patients.

Changes in Dickkopf-1, but Not Sclerostin, in Gingival Crevicular Fluid Are Associated with Peroral Statin Treatment in Patients with Periodontitis.

Background and Objectives: Periodontitis is marked by the destruction of alveolar bone. Sclerostin (SOST) and dickkopf-1 (DKK-1) act as inhibitors of the Wingless-type (Wnt) signaling pathway, a key regulator of bone metabolism. Recent studies have suggested that statins play a role in bone resorption and formation by influencing Wnt signaling. The aim of this study was to determine the levels of SOST and DKK-1 in periodontal patients with and without peroral statins treatment in their therapy. Materials and Methods: A total of 79 patients with diagnosed periodontitis were divided into two groups: 39 patients on statin therapy (SP group) and 40 patients without statin therapy as a control group (P group). The periodontal clinical examination probing (pocket) depth (PD) and gingival recession (GR) were measured, and approximal plaque was detected, while vertical and horizontal bone resorption was measured using a panoramic radiograph image. Clinical attachment loss (CAL) values were calculated using PD and GR values. Gingival crevicular fluid (GCF) was collected and used for measuring SOST and DKK-1 levels. A questionnaire was used to assess lifestyle habits and statin intake. Patients' medical records were used to obtain biochemical parameters. Results: There was no significant difference in sclerostin concentration between the SP and P group. DKK-1 values were significantly higher in the SP group compared to the control group (p = 0.04). Also, PD (p = 0.001) and GR (p = 0.03) were significantly higher in the SP group. The level of DKK-1 had a positive relationship with the PD, the greater the PD, the higher the level of DKK-1 (Rho = 0.350), while there was no significant association with other parameters. Conclusions: Peroral statins in periodontal patients are associated with GCF levels of DKK-1 but not with sclerostin levels.

Renoprotective Effect of Liraglutide Is Mediated via the Inhibition of TGF-Beta 1 in an LLC-PK1 Cell Model of Diabetic Nephropathy.

Background: Recently published research demonstrated direct renoprotective effects of the glucagon-like peptide-1 receptor agonist GLP 1 RA, but the relevant molecular mechanisms are still not clear. The aim of this research was to assess the effects of Liraglutide in a cell culture model of diabetic nephropathy on cell viability, antioxidant (GSH) and transforming growth factor beta 1 (TGF- ß1) levels and extracellular matrix (ECM) expression. The metabolic activity in hyperglycemic conditions and the effect of Liraglutide treatment were assessed by measuring Akt, pAkt, GSK3ß, pGSK3ß, pSTAT3, SOCS3, iNOS and NOX4 protein expression with Western blot. F actin distribution was used to assess the structural changes of the cells upon treatment. Materials and methods: The cells were exposed to high glucose (HG30 mM) followed by 0.5 mM H2O2 and a combination of glucose and H2O2 during 24 h. Subsequently, the cells were treated with different combinations of HG30, H2O2 and Liraglutide. Cell viability was determined by an MTT colorimetric test, and the GSH, TGF-ß1 concentration and ECM expression were measured using a spectrophotometric/microplate reader assay and an ELISA kit, respectively. Western blotting was used to detect the protein level of Akt, pAkt, GSK3ß, pGSK3ß, pSTAT3, SOCS3, iNOS and NOX4. The F-actin cytoskeleton was visualized with Phalloidin stain and subsequently quantified. Results: Cell viability was decreased as well as GSH levels in cells treated with a combination of HG30/H2O2, and HG30 alone (p < 0.001). The addition of Liraglutide improved the viability in cells treated with HG30, but it did not affect the cell viability in the cell treated with the addition of H2O2. GSH increased with the addition of Liraglutide in HG30/H2O2 (p < 0.001) treated cells, with no effect in cells treated only with HG30. TGF-ß1 levels (p < 0.001) were significantly increased in HG30 and HG30/H2O2. The addition of Liraglutide significantly decreased the TGF-ß1 levels (p < 0.01; p < 0.05) in all treated cells. The synthesis of collagen was significantly increased in HG30/H2O2 (p < 0.001), while the addition of Liraglutide in HG30/H2O2 significantly decreased collagen (p < 0.001). Akt signaling was not significantly affected by treatment. The GSK3b and NOX4 levels were significantly reduced (p < 0.01) after the peroxide and glucose treatment, with the observable restoration upon the addition of Liraglutide suggesting an important role of Liraglutide in oxidative status regulation and mitochondrial activity. The treatment with Liraglutide significantly upregulated STAT3 (p < 0.01) activity, with no change in SOCS3 indicating a selective regulation of the STAT 3 signaling pathway in glucose and the oxidative overloaded environment. A significant reduction in the distribution of F-actin was observed in cells treated with HG30/H2O2 (p < 0.01). The addition of Liraglutide to HG30-treated cells led to a significant decrease of distribution of F-actin (p < 0.001). Conclusion: The protective effect of Liraglutide is mediated through the inhibition of TGF beta, but this effect is dependent on the extent of cellular damage and the type of toxic environment. Based on the WB analysis we have revealed the signaling pathways involved in cytoprotective and cytotoxic effects of the drug itself, and further molecular studies in vitro and vivo are required to elucidate the complexity of the pathophysiological mechanisms of Liraglutide under conditions of hyperglycemia and oxidative stress.

Liraglutide Exerts Protective Effects by Downregulation of PPARγ, ACSL1 and SREBP-1c in Huh7 Cell Culture Models of Non-Alcoholic Steatosis and Drug-Induced Steatosis.

(1) Background: With the aging of the population and polypharmacy encountered in the elderly, drug-induced steatosis (DIS) has become frequent cause of non-alcoholic steatosis (NAS). Indeed, NAS and DIS may co-exist, making the ability to distinguish between the entities ever more important. The aim of our study was to study cell culture models of NAS and DIS and determine the effects of liraglutide (LIRA) in those models. (2) Methods: Huh7 cells were treated with oleic acid (OA), or amiodarone (AMD) to establish models of NAS and DIS, respectively. Cells were treated with LIRA and cell viability was assessed by MTT, lipid accumulation by Oil-Red-O staining and triglyceride assay, and intracellular signals involved in hepatosteatosis were quantitated by RT-PCR. (3) Results: After exposure to various OA and AMD concentrations, those that achieved 80% of cells viabilities were used in further experiments to establish NAS and DIS models using 0.5 mM OA and 20 µM AMD, respectively. In both models, LIRA increased cell viability (p < 0.01). Lipid accumulation was increased in both models, with microsteatotic pattern in DIS, and macrosteatotic pattern in NAS which corresponds to greater triglyceride accumulation in latter. LIRA ameliorated these changes (p < 0.001), and downregulated expression of lipogenic ACSL1, PPARγ, and SREBP-1c pathways in the liver (p < 0.01) (4) Conclusions: LIRA ameliorates hepatocyte steatosis in Huh7 cell culture models of NAS and DIS.

Expression of Oxidative Stress and Inflammation-Related Genes in Nasal Mucosa and Nasal Polyps from Patients with Chronic Rhinosinusitis.

Chronic rhinosinusitis (CRS) is a prevalent, multifaceted inflammatory condition affecting the nasal cavity and the paranasal sinuses, frequently accompanied by formation of nasal polyps (CRSwNP). This apparently uniform clinical entity is preceded by heterogeneous changes in cellular and molecular patterns, suggesting the presence of multiple CRS endotypes and a diverse etiology. Alterations of the upper airway innate defense mechanisms, including antimicrobial and antioxidant capacity, have been implicated in CRSwNP etiology. The aim of this study was to investigate mRNA expression patterns of antioxidative enzymes, including superoxide dismutase (SOD) and peroxiredoxin-2 (PRDX2), and innate immune system defense players, namely the bactericidal/permeability-increasing fold-containing family A, member 1 (BPIFA1) and PACAP family members, particularly adenylate-cyclase-activating polypeptide receptor 1 (ADCYAP1) in nasal mucosa and nasal polyps from CRSwNP patients. Additional stratification based on age, sex, allergic comorbidity, and disease severity was applied. The results showed that ADCYAP1, BPIFA1, and PRDX2 transcripts are differentially expressed in nasal mucosa and scale with radiologically assessed disease severity in CRSwNP patients. Sinonasal transcriptome is not associated with age, sex, and smoking in CRSwNP. Surgical and postoperative corticosteroid (CS) therapy improves endoscopic appearance of the mucosa, but variably reverses target gene expression patterns in the nasal cavity of CRSwNP patients. Transcriptional cross-correlations analysis revealed an increased level of connectedness among differentially expressed genes under inflammatory conditions and restoration of basic network following CS treatment. Although results of the present study imply a possible engagement of ADCYAP1 and BPIFA1 as biomarkers for CRSwNP, a more profound study taking into account disease severity and CRSwNP endotypes prior to the treatment would provide additional information on their sensitivity.

Pretreatment of Garlic Oil Extracts Hampers Epithelial Damage in Cell Culture Model of Peptic Ulcer Disease.

Background and Objectives: Peptic ulcer disease is a chronic disease affecting up to 10% of the world's population. Proton pump inhibitors, such as lansoprazole are the gold standard in the treatment of ulcer disease. However, various studies have shown the effectiveness of garlic oil extracts in the treatment of ulcer disease. A cellular model can be established in the human gastric cell line by sodium taurocholate. The aim of this study was to explore the effects of garlic oil extracts pretreatment and LPZ addition in the cell culture model of peptic ulcer disease by examining oxidative stress and F-actin distribution. Materials and Methods: Evaluation was performed by determination of glutathione and prostaglandin E2 concentrations by ELISA; human gastric cell line proliferation by cell counting; expression of ATP-binding cassette, sub-family G, member 2; nuclear factor kappa B subunit 2 by RT PCR; and F-actin cytoskeleton visualization by semi-quantification of Rhodamine Phalloidin stain. Results: Our results showed significant reduction of cell damage after sodium taurocholate incubation when the gastric cells were pretreated with lansoprazole (p < 0.001) and increasing concentrations of garlic oil extracts (p < 0.001). Pretreatment with lansoprazole and different concentrations of garlic oil extracts increased prostaglandin E2 and glutathione concentrations in the cell culture model of peptic ulcer disease (p < 0.001). Positive correlation of nuclear factor kappa B subunit 2 (p < 0.01) with lansoprazole and garlic oil extracts pretreatment was seen, while ATP-binding cassette, sub-family G, member 2 expression was not changed. Treatment with sodium taurocholate as oxidative stress on F actin structure was less pronounced, although the highest concentration of garlic oil extracts led to a statistically significant increase of total amount of F-actin (p < 0.001). Conclusions: Hence, pretreatment with garlic oil extracts had gastroprotective effect in the cell model of peptic ulcer disease. However, further experiments are needed to fully elucidate the mechanism of this protective role.

IMPACT OF GRAVES' DISEASE AND ANTITHYROID DRUG THERAPY ON BONE MINERAL DENSITY - PATHOPHYSIOLOGICAL MECHANISMS AND CLINICAL RELEVANCE.

Graves' disease is an autoimmune disease characterized by excessive thyroid hormone production. One of the consequences of that state can be a decrease in bone mineral density (BMD). Graves' disease is often treated with antithyroid drugs (ATD) as first line therapy, which can lead to disease remission. Moreover, recent data show that improvement in BMD can be expected. However, vitamin D deficiency can coexist along with Graves' disease, which is also involved in the process of bone remodeling. It is still not known whether lower values of vitamin D can contribute to onset of Graves' disease and if its supplementation might be helpful in therapy for hyperthyroidism. In the past couple of decades, osteopenia and osteoporosis have become a major health burden not only in post-menopausal women but also as a result of other diseases, leading to extensive research into various pathophysiological mechanisms responsible for bone remodeling. The Wnt (wingless integrated) signaling pathway is a very important factor in bone homeostasis, especially the canonical pathway. Present data indicate that stimulation of the Wnt pathway leads to bone mass increase and, in contrast, its inhibition leads to bone mass decrease. Hence, inhibitors of the canonical Wnt pathway became the focus of interest, in particular sclerostin and dickkopf 1 (DKK1). Hyperthyroidism and osteopenia/osteoporosis are quite common today and can coexist together or as separate entities. In this article, we aimed to give an overview of possible associations and potential mutual pathophysiological mechanisms.

Renal Benefits of SGLT 2 Inhibitors and GLP-1 Receptor Agonists: Evidence Supporting a Paradigm Shift in the Medical Management of Type 2 Diabetes.

Diabetic nephropathy (DN) is one of the most perilous side effects of diabetes mellitus type 1 and type 2 (T1DM and T2DM).). It is known that sodium/glucose cotransporter 2 inhibitors (SGLT 2i) and glucagone like peptide-1 receptor agonists (GLP-1 RAs) have renoprotective effects, but the molecular mechanisms are still unknown. In clinical trials GLP-1 analogs exerted important impact on renal composite outcomes, primarily on macroalbuminuria, possibly through suppression of inflammation-related pathways, however enhancement of natriuresis and diuresis is also one of possible mechanisms of nephroprotection. Dapagliflozin, canagliflozin, and empagliflozin are SGLT2i drugs, useful in reducing hyperglycemia and in their potential renoprotective mechanisms, which include blood pressure control, body weight loss, intraglomerular pressure reduction, and a decrease in urinary proximal tubular injury biomarkers. In this review we have discussed the potential synergistic and/or additive effects of GLP 1 RA and SGLT2 inhibitors on the primary onset and progression of kidney disease, and the potential implications on current guidelines of diabetes type 2 management.

LIFESTYLE RISK FACTORS AND BONE MASS IN RECURRENT STONE-FORMING PATIENTS: A CROSS-SECTIONAL STUDY IN 144 SUBJECTS.

Patients with urolithiasis, particularly hypercalciuria, may have reduced bone mineral density (BMD). There are numerous risk factors contributing to reduction of BMD such as advanced age, sedentary lifestyle, smoking, low calcium intake, etc. The aim of our study was to investigate the association of lifestyle risk factors and daily intake of milk and dairy products with determinants of BMD in a group of recurrent calcium stone formers (RSF) compared with healthy subjects (HS). The study was carried out at the Department of Mineral Research, Faculty of Medicine in Osijek, Croatia. The study included 144 subjects, i.e. 56 RSF and 78 HS. BMD was assessed by dual-energy x-ray absorptiometry. A standard self-reported questionnaire was used to collect data on lifestyle risk factors. Current dietary intake was assessed by personal interview that included questions about milk and dairy product intake. Low BMD was observed in 44.64% of RSF and 35.90% of HS. RSF consumed significantly less milk and dairy products than HS. Calcium restriction in dietary recommendations might be unnecessary due to the impact on bone mineral loss in RSF and dual-energy x-ray absorptiometry should be included in the routine evaluation of RSF.

Hyperthyroidism and Wnt Signaling Pathway: Influence on Bone Remodeling.

Graves' disease is an autoimmune disease of the thyroid gland, characterized by increased production of thyroid hormones, which can affect many different organ systems in the body. Among other problems, it can cause disorders of the skeletal system, shortening the bone remodeling cycle and causing a decrease in bone density. The Wnt cascade signaling pathway and the ß-catenin, as a part of the canonical Wnt pathway, also play roles in maintaining bone mass. Inhibition of the Wnt pathway can cause bone loss, and its stimulation can increase it. The Wnt signaling pathway influences the effectiveness of thyroid hormones by affecting receptors for thyroid hormones and deiodinase, while thyroid hormones can change levels of ß-catenin within the cell cytoplasm. This indicates that the Wnt pathway and thyroid hormone levels, including hyperthyroidism, are linked and may act together to change bone density. In this review article, we attempt to explain the interplay between thyroid hormones and the Wnt pathway on bone density, with a focus on directions for further research and treatment options.

Wnt Inhibitors and Bone Mineral Density in Patients with Graves' Disease Treated with Antithyroid Drugs: A Preliminary Prospective Study.

This study aimed to investigate the association of Wnt inhibitors with thyroid hormones, bone turnover markers, and bone mineral density (BMD) in patients with newly diagnosed Graves' disease (GD) at the beginning of the antithyroid treatment and after a follow-up period of one year. The study included 37 patients with newly diagnosed GD who were treated with antithyroid drugs (ATD). At baseline and after one year, thyroid hormones and thyroid-stimulating hormone (TSH), serum concentrations of sclerostin, and Dickkopf-1 (DKK1) were measured by an enzyme-linked immunosorbent assay (ELISA). In addition, BMD was measured by dual-energy X-ray absorptiometry (DXA), and markers of bone turnover including osteocalcin (OC), beta-cross laps (ß-CTX), and deoxypyridinoline (DPD) were determined. After one year of ATD therapy sclerostin levels were significantly decreased (p < 0.001), whereas DKK1 levels were significantly increased (p = 0.01). In addition, BMD of the lumbar spine, total hip, and femoral neck was significantly improved (p < 0.001), accompanied by an increase in OC, ß-CTX, and DPD concentrations (p < 0.001). At baseline, sclerostin levels were positively associated with free triiodothyronine (FT3). Following ATD therapy, a positive correlation was observed between FT3 and DKK1 (p = 0.003), whereas a negative correlation was found between TSH and DKK1 (p = 0.04). Correlation analysis demonstrated no association of the sclerostin and DKK1 with other bone remodeling biomarkers OC, ß-CTX, or DPD. Also, no significant correlation between sclerostin or DKK1 and T-score or BMD of the lumbar spine, hip, and femoral neck was observed at both time points. Conclusion: Observed differences in sclerostin and DKK1 serum following GD treatment indicate involvement of Wnt inhibitors in the etiopathogenesis of bone loss associated with hyperthyroidism. Furthermore, both sclerostin and DKK1 are involved in the reversal of changes in bone metabolism following ATD therapy, thus presenting potentially valuable bone remodeling markers worth further investigation.

Therapeutic Perspectives of IL1 Family Members in Liver Diseases: An Update.

Interleukin (IL) 1 superfamily members are a cornerstone of a variety of inflammatory processes occurring in various organs including the liver. Progression of acute and chronic liver diseases regardless of etiology depends on the stage of hepatocyte damage, the release of inflammatory cytokines and disturbances in gut microbiota. IL1 cytokines and receptors can have pro- or anti-inflammatory roles, even dual functionalities conditioned by the microenvironment. Developing novel therapeutic strategies to block the IL1/IL1R signaling pathways seems like a reasonable option. This mode of action is now exploited by anakinra and canakinumab, which are used to treat different inflammatory illnesses, and studies in liver diseases are on the way. In this mini review, we have focused on the IL1 superfamily members, given their crucial role in liver inflammation diseases, specifically discussing their potential role in developing new treatment strategies.

A Conceptual Model of Nurses' Turnover Intention.

The World Health Organisation predicts a lack of 15 million health professionals by 2030. The lack of licenced professionals is a problem that keeps emerging and is carefully studied on a global level. Strategic objectives aimed at stimulating employment, improving working conditions, and keeping the nurses on board greatly depends on identifying factors that contribute to their turnover. The aim of this study was to present a conceptual model based on predictors of nurses' turnover intention. Methods: A quantitative, non-experimental research design was used. A total of 308 registered nurses (RNs) took part in the study. The Multidimensional Work Motivation Scale (MWMS) and Practice Environment Scale of the Nursing Work Index (PES-NWI) were used. Results: The conceptual model, based on the binary regression models, relies on two direct significant predictors and four indirect significant predictors of turnover intention. The direct predictors are job satisfaction (OR = 0.23) and absenteeism (OR = 2.5). Indirect predictors that affect turnover intention via job satisfaction are: amotivation (OR = 0.59), identified regulation (OR = 0.54), intrinsic motivation (OR = 1.67), and nurse manager ability, leadership and support of nurses (OR = 1.51). Conclusions: The results of the study indicate strategic issues that need to be addressed to retain the nursing workforce. There is a need to ensure positive perceptions and support from managers, maintain intrinsic motivation, and promote even higher levels of motivation to achieve satisfactory levels of job satisfaction.

Molecular Mechanisms Linking Empagliflozin to Renal Protection in the LLC-PK1 Model of Diabetic Nephropathy.

Aims: Chronic diabetes complications, including diabetic nephropathy (DN), frequently result in end-stage renal failure. This study investigated empagliflozin (SGLT2i) effects on collagen synthesis, oxidative stress, cell survival, and protein expression in an LLC-PK1 model of DN. Methods: Combinations of high glucose (HG) and increasing empagliflozin concentrations (100 nM and 500 nM), as well as combinations of HG, H2O2, and empagliflozin, were used for cell culture treatment. The cell viability, glutathione (tGSH), ECM expression, and TGF-ß1 concentration were measured. In addition, the protein expression of Akt, pAkt, GSK3, pGSK3, pSTAT3, and SMAD7 was determined. Results: The addition of both concentrations of empagliflozin to cells previously exposed to glucose and oxidative stress generally improved cell viability and increased GSH levels (p < 0.001, p < 0.05). In HG30/H2O2/Empa500-treated cells, significant increase in pSTAT3, pGSK3ß, GSK3ß, SMAD7, and pAKT levels (p < 0.001, p < 0.001, p < 0.05) was observed except for AKT. Lower drug concentrations did not affect the protein expression levels. Furthermore, empagliflozin treatment (100 nM and 500 nM) of HG30/H2O2-injured cells led to a decrease in TGF-ß1 levels (p < 0.001). In cells exposed to oxidative stress and hyperglycemia, collagen production remained unchanged. Conclusion: Renoprotective effects of empagliflozin, in this LLC-PK1 cell model of DN, are mediated via activation of the Akt/GSK-3 signalling pathway, thus reducing oxidative stress-induced damage, as well as enhanced SMAD7 expression leading to downregulation of TGF-ß1, one of the key mediators of inflammation and fibrosis.

Keratocan is expressed by osteoblasts and can modulate osteogenic differentiation.

Keratocan is an extracellular matrix protein that belongs to the small leucine-rich proteoglycan family that also includes lumican, biglycan, decorin, mimecan, and fibromodulin. Members of this family are known to play a role in regulating cellular processes such as proliferation and modulation of osteoprogenitor lineage differentiation. The aims of this study were to evaluate the expression pattern of the keratocan within the osteoprogenitor lineage and to assess its role in regulating osteoblast maturation and function. Results from gene expression analyses of cells at different maturation stages within the osteoblast lineage indicate that keratocan is differentially expressed by osteoblasts and shows little or no expression by osteocytes. During primary osteoblast cultures, high keratocan mRNA expression was observed on day 14, whereas lower expression was detected at days 7 and 21. To assess the effects of keratocan on osteoprogenitor cell differentiation, we evaluated primary calvarial cell cultures from keratocan-deficient mice. The mineralization of calvarial osteoblast cultures derived from keratocan null (Kera-/-) mice was lower than in wild-type osteoblast cultures. Furthermore, analysis of RNA derived from Kera-/- calvarial cell cultures showed a reduction in the mature osteoblast differentiation markers, that is, bone sialoprotein and osteocalcin. In addition, we have evaluated the bone formation in keratocan-deficient mice. Histomorphometric analysis indicated that homozygous knockout mice have significantly decreased rates of bone formation and mineral apposition. Taken together, our results demonstrate the expression of keratocan by osteoblast lineage cells and its ability to modulate osteoblast function.

Molecular Mechanisms of Resistance to Immune Checkpoint Inhibitors in Melanoma Treatment: An Update.

Over the past decade, immune checkpoint inhibitors (ICI) have revolutionized the treatment of advanced melanoma and ensured significant improvement in overall survival versus chemotherapy. ICI or targeted therapy are now the first line treatment in advanced melanoma, depending on the tumor v-raf murine sarcoma viral oncogene homolog B1 (BRAF) mutational status. While these new approaches have changed the outcomes for many patients, a significant proportion of them still experience lack of response, known as primary resistance. Mechanisms of primary drug resistance are not fully elucidated. However, many alterations have been found in ICI-resistant melanomas and possibly contribute to that outcome. Furthermore, some tumors which initially responded to ICI treatment ultimately developed mechanisms of acquired resistance and subsequent tumor progression. In this review, we give an overview of tumor primary and acquired resistance mechanisms to ICI and discuss future perspectives with regards to new molecular targets and combinatorial therapies.

Effect of COVID-19 on management of type 1 diabetes: Pushing the boundaries of telemedical healthcare.

The new coronavirus disease 2019 (COVID-19) pandemic posed a great burden on health care systems worldwide and is an enormous and real obstacle in providing needed health care to patients with chronic diseases such as diabetes. Parallel to COVID-19, there have been great advances in technology used for management of type 1 diabetes, primarily insulin pumps, sensors, integrated and closed loop systems, ambulatory glucose profile software, and smart phone apps providing necessary essentials for telemedicine implementation right at the beginning of the COVID-19 pandemic. The results of these remote interventions are reassuring in terms of glycemic management and hemoglobin A1c reductions. However, data on long-term outcomes and cost reductions are missing as well as proper technical infrastructure and government health policy support.

Hypothyroidism and Nonalcoholic Fatty Liver Disease: Pathophysiological Associations and Therapeutic Implications.

Nonalcoholic fatty liver disease (NAFLD) is a complex clinical entity which can be secondary to many other diseases including hypothyroidism, characterized by lowering of thyroid hormones and increased thyroid stimulating hormone (TSH). A lot of emerging data published recently advocates the hypothesis that hypothyroid induced NAFLD could be a separate clinical entity, even suggesting possible treatment options for NAFLD involving substitution therapy for hypothyroidism along with lifestyle modifications. In addition, a whole new field of research is focused on thyromimetics in NAFLD/NASH treatment, currently in phase 3 clinical trials. In this critical review we summarized epidemiological and pathophysiological evidence linking these two clinical entities and described specific treatment options with the accent on promising new agents in NAFLD treatment, specifically thyroid hormone receptor (THR) agonist and its metabolites.

Representation of CYP3A4, CYP3A5 and UGT1A4 Polymorphisms within Croatian Breast Cancer Patients' Population.

Single nucleotide polymorphism (SNP) in genes encoding drug-metabolizing enzymes (DME) could have a critical role in individual responses to anastrozole. Frequency of CYP3A4*1B, CYP3A5*3 and UGT1A4*2 SNPs in 126 Croatian breast cancer (BC) patients and possible association with anastrozole-induced undesirable side effects were analyzed. Eighty-two postmenopausal patients with estrogen receptor (ER)-positive BC treated with anastrozole and 44 postmenopausal ER-positive BC patients before hormonal adjuvant therapy were included in the study. Genomic DNA was genotyped by TaqMan Real-Time PCR. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. The homozygotes for the variant G allele of CYP3A5*3 were predominant (88%), and the homozygotes for the reference A allele were not detected. While homozygotes for the variant G allele of CYP3A4*1B were not detected, predominantly wild type homozygotes for A allele (94%) were present. CYP3A4*1B and CYP3A5*3 SNPs were in 84.3% linkage disequilibrium (D' = 0.843) and 95.1% (D' = 0.951) in group treated with anastrozole and w/o treatment, respectively. Homozygotes for the A allele of UGT1A4*2 were not detected in our study groups. Although the variant CYP3A5*3 allele, which might result in poor metabolizer phenotype and more pronounced side effects, was predominant, significant association with BMD changes induced by anastrozole were not confirmed.