The Current and Promising Oral Delivery Methods for Protein- and Peptide-Based Drugs.

Drugs based on peptides and proteins (PPs) have been widely used in medicine, beginning with insulin therapy in patients with diabetes mellitus over a century ago. Although the oral route of drug administration is the preferred one by the vast majority of patients and improves compliance, medications of this kind due to their specific chemical structure are typically delivered parenterally, which ensures optimal bioavailability. In order to overcome issues connected with oral absorption of PPs such as their instability depending on digestive enzymes and pH changes in the gastrointestinal (GI) system on the one hand, but also their limited permeability across physiological barriers (mucus and epithelium) on the other hand, scientists have been strenuously searching for novel delivery methods enabling peptide and protein drugs (PPDs) to be administered enterally. These include utilization of different nanoparticles, transport channels, substances enhancing permeation, chemical modifications, hydrogels, microneedles, microemulsion, proteolytic enzyme inhibitors, and cell-penetrating peptides, all of which are extensively discussed in this review. Furthermore, this article highlights oral PP therapeutics both previously used in therapy and currently available on the medical market.

Impact of Glucagon-Like Peptide 1 Receptor Agonists on Biochemical Markers of the Initiation of Atherosclerotic Process.

Atherosclerosis stands out as one of the leading causes of global mortality. The inflammatory response against vascular wall components plays a pivotal role in the atherogenic process. The initiation of this process is notably driven by oxidized low-density lipoprotein (oxLDL) and a range of pro-inflammatory cytokines, with interleukin-1ß (Il-1ß) and tumor necrosis factor α (TNFα) emerging as particularly significant in the early stages of atherosclerotic plaque formation. In recent years, researchers worldwide have been diligently exploring innovative therapeutic approaches for metabolic diseases, recognizing their impact on the atherogenesis process. Our study aimed to investigate the influence of glucagon-like peptide 1 receptor agonists (GLP-1RA) on cytokine concentrations associated with the initiation of atherosclerotic plaque formation in a group of patients with type 2 diabetes and dyslipidemia. The study encompassed 50 subjects aged 41-81 (mean: 60.7), all diagnosed with type 2 diabetes, dyslipidemia and confirmed atherosclerosis based on B-mode ultrasound. Following a 180-day treatment with dulaglutide or semaglutide, we observed a statistically significant reduction in biochemical markers (oxLDL, TNFα and Il-1ß) associated with the initiation of the atherosclerotic process (p < 0.001) within our study group. In addition to the already acknowledged positive effects of GLP-1RA on the metabolic parameters of treated patients, these drugs demonstrated a notable reduction in proinflammatory cytokine concentrations and may constitute an important element of therapy aimed at reducing cardiovascular risk.

Molecular Mechanisms behind Obesity and Their Potential Exploitation in Current and Future Therapy.

Obesity is a chronic disease caused primarily by the imbalance between the amount of calories supplied to the body and energy expenditure. Not only does it deteriorate the quality of life, but most importantly it increases the risk of cardiovascular diseases and the development of type 2 diabetes mellitus, leading to reduced life expectancy. In this review, we would like to present the molecular pathomechanisms underlying obesity, which constitute the target points for the action of anti-obesity medications. These include the central nervous system, brain-gut-microbiome axis, gastrointestinal motility, and energy expenditure. A significant part of this article is dedicated to incretin-based drugs such as GLP-1 receptor agonists (e.g., liraglutide and semaglutide), as well as the brand new dual GLP-1 and GIP receptor agonist tirzepatide, all of which have become "block-buster" drugs due to their effectiveness in reducing body weight and beneficial effects on the patient's metabolic profile. Finally, this review article highlights newly designed molecules with the potential for future obesity management that are the subject of ongoing clinical trials.

The Application of Peptide Nucleic Acids (PNA) in the Inhibition of Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) Gene Expression in a Cell-Free Transcription/Translation System.

Proprotein convertase subtilisin/kexin 9 (PCSK9) is a protein that plays a key role in the metabolism of low-density lipoprotein (LDL) cholesterol. The gain-of-function mutations of the PCSK9 gene lead to a reduced number of surface LDL receptors by binding to them, eventually leading to endosomal degradation. This, in turn, is the culprit of hypercholesterolemia, resulting in accelerated atherogenesis. The modern treatment for hypercholesterolemia encompasses the use of biological drugs against PCSK9, like monoclonal antibodies and gene expression modulators such as inclisiran-a short, interfering RNA (siRNA). Peptide nucleic acid (PNA) is a synthetic analog of nucleic acid that possesses a synthetic peptide skeleton instead of a phosphate-sugar one. This different structure determines the unique properties of PNA (e.g., neutral charge, enzymatic resistance, and an enormously high affinity with complementary DNA and RNA). Therefore, it might be possible to use PNA against PCSK9 in the treatment of hypercholesterolemia. We sought to explore the impact of three selected PNA oligomers on PCSK9 gene expression. Using a cell-free transcription/translation system, we showed that one of the tested PNA strands was able to reduce the PCSK9 gene expression down to 74%, 64%, and 68%, as measured by RT-real-time PCR, Western blot, and HPLC, respectively. This preliminary study shows the high applicability of a cell-free enzymatic environment as an efficient tool in the initial evaluation of biologically active PNA molecules in the field of hypercholesterolemia research. This cell-free approach allows for the omission of the hurdles associated with transmembrane PNA transportation at the early stage of PNA selection.

Influence of Dulaglutide on Serum Biomarkers of Atherosclerotic Plaque Instability: An Interventional Analysis of Cytokine Profiles in Diabetic Subjects-A Pilot Study.

Background and Objectives: The rise in global diabetes cases, reaching a staggering 529 million in 2021 from 108 million in 1980, underscores the urgency of addressing its complications, notably macrovascular ones like coronary artery, cerebrovascular, and peripheral artery diseases, which contribute to over 50% of diabetes mortality. Atherosclerosis, linked to hyperglycemia-induced endothelial dysfunction, is pivotal in cardiovascular disease development. Cytokines, including pentraxin 3 (PTX3), copeptin, lipoprotein(a) [Lp(a)], and matrix metalloproteinase-9 (MMP-9), influence atherosclerosis progression and plaque vulnerability. Inhibiting atherosclerosis progression is crucial, especially in diabetic individuals. Glucagon-like peptide 1 receptor agonists (GLP-1 RAs), increasingly used for type 2 diabetes, show promise in reducing the cardiovascular risk, sparking interest in their effects on atherogenesis. This study sought to examine the effects of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on biomarkers that indicate the instability of atherosclerotic plaques. These biomarkers include pentraxin 3 (PTX3), copeptin (CPC), matrix metalloproteinase-9 (MMP-9), and lipoprotein(a) [Lp(a)]. Materials and Methods: A total of 34 participants, ranging in age from 41 to 81 years (with an average age of 61), who had been diagnosed with type 2 diabetes mellitus (with a median HbA1c level of 8.8%), dyslipidemia, and verified atherosclerosis using B-mode ultrasonography, were included in the study. All subjects were eligible to initiate treatment with a GLP-1 RA-dulaglutide. Results: Significant reductions in anthropometric parameters, blood pressure, fasting glucose levels, and HbA1c levels were observed posttreatment. Moreover, a notable decrease in biochemical markers associated with atherosclerotic plaque instability, particularly PTX3 and MMP-9 (p < 0.001), as well as Lp(a) (p < 0.05), was evident following the GLP-1 RA intervention. Conclusions: These findings underscore the potential of GLP-1 RAs in mitigating atherosclerosis progression and plaque vulnerability, thus enhancing cardiovascular outcomes in individuals with type 2 diabetes mellitus.

Rosuvastatin Potentiates Gonadotropin-Lowering Effects of Metformin in Postmenopausal Women: A Pilot Study.

INTRODUCTION: Metformin reduces elevated levels of FSH and LH. In some studies, gonadotroph secretory function was inhibited by statins. The aim of the present study was to investigate whether statin therapy modulates the impact of metformin on hypothalamic-pituitary-gonadal axis activity in postmenopausal women. METHODS: The study population included 60 postmenopausal women with prediabetes, 40 of whom, because of high cardiovascular risk, received rosuvastatin (20-40 mg daily). One group of rosuvastatin-treated women (group A, n = 23) and all statin-naïve patients (group B, n = 20) were matched for age, glucose homeostasis markers, and gonadotropin levels. Over the entire study period (6 months), these women received metformin. The third group (group C) included 17 rosuvastatin-treated women refusing metformin treatment. We assessed baseline and follow-up plasma lipids, glucose homeostasis markers, and concentrations of FSH, LH, thyrotropin, prolactin, adrenocorticotropic hormone (ACTH), insulin-like growth factor-1, estradiol, progesterone, and anti-Müllerian hormone (in selected patients). RESULTS: Fifty-three women (18 in groups A and B and 17 in group C) completed the study. At study entry, rosuvastatin-treated and statin-naïve women differed in levels of total cholesterol, LDL-cholesterol, and ACTH. In statin-naïve women, metformin reduced FSH levels and tended to reduce LH levels. In rosuvastatin-treated women, metformin decreased FSH and LH levels, and both effects were stronger than in statin-naïve women. Although observed in both groups, the impact on glucose homeostasis markers was more pronounced in individuals not receiving statin therapy. Metformin treatment did not affect circulating levels of lipids, thyrotropin, prolactin, ACTH, insulin-like growth factor-1, estradiol, and anti-Müllerian hormone. In group C, plasma lipids, glucose homeostasis markers, and hormone levels remained at a similar level throughout the study period. CONCLUSION: The obtained results indicate that statin therapy may enhance gonadotropin-lowering effects of metformin.

Cardiometabolic Risk Factors in Atorvastatin-Treated Women with Euthyroid Autoimmune Thyroiditis.

INTRODUCTION: Autoimmune thyroiditis seems to be associated with increased cardiometabolic risk. Statins, the mainstay of cardiovascular risk reduction and prevention, were found to reduce thyroid antibody titers. The aim of this study was to investigate plasma markers of cardiometabolic risk in statin-treated women with thyroid autoimmunity. METHODS: We compared two matched groups of euthyroid women with hypercholesterolemia receiving atorvastatin treatment: subjects with autoimmune (Hashimoto's) thyroiditis (group A, n = 29) and subjects without thyroid pathology (group B, n = 29). Plasma lipids, glucose homeostasis markers, as well as circulating levels of uric acid, high-sensitivity C-reactive protein (hsCRP), fibrinogen, homocysteine, and 25-hydroxyvitamin D were measured before atorvastatin treatment and 6 months later. RESULTS: At entry, both groups differed in antibody titers, insulin sensitivity, and plasma levels of uric acid, hsCRP, fibrinogen, homocysteine, and 25-hydroxyvitamin D. Atorvastatin-induced reduction in hsCRP and homocysteine, but not in total cholesterol and LDL-cholesterol, was more pronounced in group B than in group A. Only in group B, the drug decreased uric acid and fibrinogen and increased 25-hydroxyvitamin D. In group A, atorvastatin reduced insulin responsiveness. CONCLUSION: The obtained results indicate that euthyroid women with Hashimoto's thyroiditis may benefit to a lesser degree from atorvastatin treatment than other populations of women with hypercholesterolemia.

The Impact of Atorvastatin on Cardiometabolic Risk Factors in Sisters of Women with Polycystic Ovary Syndrome.

INTRODUCTION: Polycystic ovary syndrome (PCOS) is a frequent endocrinopathy in young women with significantly increased cardiometabolic risk. Siblings of women with this disorder are at increased risk of insulin resistance and androgen excess. The current study was aimed at investigating cardiometabolic effects of atorvastatin in sisters of women with PCOS. METHODS: This prospective observational study compared two age-, body mass index-, blood pressure-, and plasma lipid-matched groups of women with hypercholesterolemia: sisters of PCOS probands (group A) and unrelated control subjects (group B), receiving atorvastatin (40 mg daily). Plasma lipids, glucose homeostasis markers, concentrations of sex hormones, high-sensitivity C-reactive protein (hsCRP), homocysteine, fibrinogen and uric acid, and the urinary albumin-to-creatinine ratio (UACR) were measured before entering the study and 6 months later. RESULTS: Both groups differed in the degree of insulin resistance, testosterone, free androgen index (FAI), circulating levels of hsCRP and homocysteine, and UACR. There were no between-group differences in the impact of atorvastatin on plasma lipids. Despite reducing hsCRP and homocysteine in both groups of women, the effect on these biomarkers was stronger in group B than in group A. Only in group B, atorvastatin did reduce fibrinogen, uric acid, and UACR. Only in group A, atorvastatin did worsen insulin sensitivity and tended to reduce testosterone and FAI. The impact of atorvastatin on hsCRP, homocysteine, fibrinogen, uric acid, and UACR inversely correlated with testosterone and FAI. CONCLUSION: The obtained results suggest that sisters of women with PCOS may benefit to a lesser degree from atorvastatin treatment than other women.

Myo-Inositol Potentiates the Inhibitory Effect of Metformin on Prolactin Levels.

INTRODUCTION: Metformin was found to reduce elevated levels of anterior pituitary hormones. Its thyrotropin-lowering effect was more pronounced in individuals receiving myo-inositol. The aim of the present study was to investigate whether the concomitant supplementation of myo-inositol determines the impact of metformin on prolactin levels. METHODS: The study population consisted of two groups of women with mild-to-moderate hyperprolactinemia. Group 1 included 24 individuals receiving myo-inositol preparations (2 g daily for at least 6 months), while 24 inositol-naïve women belonged to group 2. Both groups were matched for age, insulin sensitivity, and prolactin concentration. For the following 6 months, all women were treated with metformin (1.7 daily). Plasma glucose levels, the homeostatic model assessment of insulin resistance ratio (HOMA-IR), glycated hemoglobin, as well as plasma levels of total prolactin, monomeric prolactin, thyrotropin, free thyroid hormones, adrenocorticotropic hormone, and insulin-like growth factor-1 were measured at baseline and after 6 months of metformin treatment. RESULTS: Metformin reduced plasma glucose, HOMA-IR, and glycated hemoglobin in both study groups, but this effect was more pronounced in group 1 than group 2. Treatment-induced changes in total and monomeric prolactin levels were significant only in group 1. There were no differences between follow-up and baseline values of thyrotropin, free thyroxine, free tri-iodothyronine, adrenocorticotropic hormone, and insulin-like growth factor-1. Treatment-induced changes in prolactin concentration correlated with baseline prolactin levels, baseline values of HOMA-IR, and the impact of treatment on HOMA-IR. DISCUSSION: The obtained results suggest that myo-inositol supplementation potentiates the inhibitory effect of metformin on prolactin levels in women with hyperprolactinemia.

Inclisiran-A Revolutionary Addition to a Cholesterol-Lowering Therapy.

Hypercholesterolemia plays a crucial role in the development of atherosclerosis, but it remains an undertreated and underdiagnosed disease. Taking into consideration the high prevalence of lipid disorders, long duration of the asymptomatic course of the disease, life-threatening complications resulting from inaccurate therapy, and stringent treatment goals concerning LDL cholesterol level in the prevention of cardiovascular events, novel lipid-lowering therapies have been introduced in the last few years. In this article, a drug belonging to the group of small interfering RNA (siRNA) called inclisiran is described. It is a novel molecule that increases the number of LDL receptors (LDLRs) on the surface of hepatic cells by preventing the formation of proprotein convertase subtilisin/kexin type 9 (PCSK9) responsible for the degradation of LDLRs. With great potential for lowering plasma LDL cholesterol level, high liver specificity, comfortable dosing regimen, and good tolerance without significant adverse effects, it could play an important part in future hypolipemic therapies.

The Effect of PCSK9 Inhibition on the Stabilization of Atherosclerotic Plaque Determined by Biochemical and Diagnostic Imaging Methods.

Atherosclerosis is a multifactorial, progressive, chronic inflammatory disease. Ultrasound and magnetic resonance imaging are the most accurate predictors of atherosclerotic plaque instability (MRI). Cytokines such as osteopontin, osteoprotegerin, and metalloproteinase 9 could be used as the most recent markers to identify and track the efficacy of anti-atherosclerotic therapy. Patients with USG and MRI-verified unstable atherosclerotic plaque were included in the study. Biomarker concentrations were measured and compared before and after PCSK9 inhibitor therapy. Additionally, concentrations prior to treatment were correlated with MRI images of the carotid artery. After treatment with alirocumab, the concentrations of MMP-9 (p < 0.01) and OPN, OPG (p < 0.05) decreased significantly. Furthermore, the results of OPN, OPG, and MMP 9 varied significantly depending on the type of atherosclerotic plaque in the MRI assay. In stable atherosclerotic plaques, the concentrations of OPN and OPG were greater (p < 0.01), whereas the concentration of MMP9 correlated with the instability of the plaque (p < 0.05). We demonstrated, probably for the first time, that alirocumab therapy significantly decreased the serum concentration of atherosclerotic plaque markers. In addition, we demonstrated the relationship between the type of atherosclerotic plaque as determined by carotid MRI and the concentration of these markers.

Potential Therapeutic Strategies in the Treatment of Metabolic-Associated Fatty Liver Disease.

Metabolic-associated Fatty Liver Disease is one of the outstanding challenges in gastroenterology. The increasing incidence of the disease is undoubtedly connected with the ongoing obesity pandemic. The lack of specific symptoms in the early phases and the grave complications of the disease require an active approach to prompt diagnosis and treatment. Therapeutic lifestyle changes should be introduced in a great majority of patients; but, in many cases, the adherence is not satisfactory. There is a great need for an effective pharmacological therapy for Metabolic-Associated Fatty Liver Disease, especially before the onset of steatohepatitis. Currently, there are no specific recommendations on the selection of drugs to treat liver steatosis and prevent patients from progression toward more advanced stages (steatohepatitis, cirrhosis, and cancer). Therefore, in this Review, we provide data on the clinical efficacy of therapeutic interventions that might improve the course of Metabolic-Associated Fatty Liver Disease. These include the drugs used in the treatment of obesity and hyperlipidemias, as well as affecting the gut microbiota and endocrine system, and other experimental approaches, including functional foods. Finally, we provide advice on the selection of drugs for patients with concomitant Metabolic-Associated Fatty Liver Disease.

Cabergoline-Induced Hypoprolactinemia May Attenuate Cardiometabolic Effects of Atorvastatin: A Pilot Study.

INTRODUCTION: Hypoprolactinemia, which is usually a consequence of treatment with inadequate high doses of dopaminergic agents, is a poorly understood clinical condition. The aim of the current study was to investigate whether the cardiometabolic effects of statin therapy differ between patients with low prolactin production and patients with normal levels of this hormone. METHODS: We studied two groups of cabergoline-treated premenopausal women with hypercholesterolemia matched for age, plasma lipids, cabergoline dose, and treatment duration: 11 women with hypoprolactinemia (group A) and 15 women with plasma levels of this hormone within the reference range (group B). The control group (C) included 25 dopaminergic-naïve normoprolactinemic women, matched for age and lipid levels. Plasma lipids, insulin sensitivity, and levels of uric acid, high-sensitivity C-reactive protein (hsCRP), fibrinogen, homocysteine, and 25-hydroxyvitamin D were measured before and after 14-week treatment with atorvastatin (20 mg daily). RESULTS: Patients with hypoprolactinemia were more insulin-resistant, had lower values of total testosterone and free androgen index, and had higher levels of hsCRP and fibrinogen than individuals with normal prolactin levels. Although atorvastatin reduced total and LDL cholesterol and hsCRP in all study groups, this effect was stronger in groups B and C than in group A. Only in groups B and C, the drug decreased uric acid, fibrinogen, and homocysteine and increased 25-hydroxyvitamin D. In turn, only in group A, atorvastatin worsened insulin sensitivity and reduced free androgen index. CONCLUSION: Coexisting hypoprolactinemia may have an unfavorable impact on the pleiotropic effects of statins.

Gluten-free diet attenuates the impact of exogenous vitamin D on thyroid autoimmunity in young women with autoimmune thyroiditis: a pilot study.

Although both exogenous vitamin D and a gluten-free diet were found to reduce thyroid antibody titers, no study investigated interactions between gluten intake and vitamin D status in patients with autoimmune thyroid disorders. The aim of the present study was to assess whether the gluten-free diet determines the effect of vitamin D treatment on thyroid autoimmunity and thyroid function in young women with autoimmune (Hashimoto's) thyroiditis. The study compared two groups of euthyroid premenopausal women with this disorder, matched for thyroid antibody titers: 31 women with non-celiac gluten sensitivity complying for at least 12 months with the gluten-free diet and 31 unaffected sisters of women with non-celiac gluten sensitivity remaining without any dietary intervention. Plasma titers of thyroid peroxidase and thyroglobulin antibodies, as well as plasma concentrations of thyrotropin, free thyroid hormones, prolactin, 25-hydroxyvitamin D and high-sensitive C-reactive protein were measured at entry and after a six-month follow-up. Moreover, at both time points, the structure parameters of thyroid homeostasis were assessed. Although exogenous vitamin D decreased titers of thyroid peroxidase and thyroglobulin antibodies and increased 25-hydroxyvitamin D levels in each treatment group, this effect was less pronounced in patients on the gluten-free diet than in patients not following any dietary recommendations. Only in the latter group of patients, vitamin D increased SPINA-GT. Treatment-induced changes in thyroid peroxidase and thyroglobulin antibodies correlated with the impact of treatment on 25-hydroxyvitamin D levels. The obtained results suggest that gluten-free diet may impair beneficial effects of exogenous vitamin D in individuals with Hashimoto's thyroiditis.

Rosuvastatin potentiates the thyrotropin-lowering effect of metformin in men with non-autoimmune subclinical hypothyroidism and prediabetes.

WHAT IS KNOWN AND OBJECTIVE: Metformin treatment decreases thyrotropin levels in individuals with hypothyroidism and this effect seems to be mediated by the 5'-adenosine monophosphate-activated protein kinase pathway in the pituitary. The activity of this pathway is also stimulated by statins. The current study was aimed at investigating whether the impact of metformin on hypothalamic-pituitary-thyroid axis activity is affected by statin use. METHODS: The study included three matched groups of men with non-autoimmune hypothyroidism and prediabetes: patients treated for at least 6 months with high-intensity rosuvastatin therapy (20-40 mg daily) [groups A (n = 24) and C (n = 19)] and men not receiving statin therapy [group B (n = 24)]. Over the entire study period (6 months), groups A and B received metformin (2.55-3 g daily). Moreover, groups A and C continued rosuvastatin therapy. The lipid profile, glucose homeostasis markers, and plasma concentrations of thyrotropin, total and free thyroid hormones, prolactin, FSH, LH, ACTH and insulin-like growth factor-1 were determined at baseline and 6 months later. RESULTS AND DISCUSSION: Fifty-nine patients completed the study. There were differences between groups A and C and group B in baseline values of total cholesterol, LDL-cholesterol, gonadotropins and ACTH. Although observed in both groups of metformin-treated patients, the effect on thyrotropin levels was more pronounced in group A than in group B. The impact on fasting glucose and insulin sensitivity was stronger in group B than group A. In turn, only in group A metformin tended to reduce gonadotropin levels. There were no differences between follow-up and baseline values of lipids, total and free thyroid hormones, prolactin, ACTH and insulin-like growth factor-1 in both these groups. In group C, all assessed variables remained at a similar level. WHAT IS NEW AND CONCLUSION: The results of the current study suggest that rosuvastatin potentiates the inhibitory effect of metformin on thyrotrope secretory function.

Differences in levothyroxine action on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity between metformin- and myo-inositol-treated women with autoimmune subclinical hypothyroidism.

WHAT IS KNOWN AND OBJECTIVE: Insulin resistance impairs the impact of levothyroxine on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity. Both metformin and myo-inositol were found to improve insulin sensitivity and to reduce thyrotropin levels in individuals with hypothyroidism. The aim of the present study was to compare the effect of levothyroxine on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity between women receiving metformin and myo-inositol. METHODS: The study included two groups of women with autoimmune hypothyroidism, treated for at least 6 months with either metformin (group A; n = 25) or myo-inositol (group B; n = 25). Both groups were matched for age, insulin sensitivity, hormone levels and antibody titers. For the following 6 months, all women received levothyroxine. Plasma levels of glucose, insulin, thyrotropin, free thyroid hormones, prolactin, 25-hydroxyvitamin D and high-sensitivity C-reactive protein (hsCRP), as well as titers of thyroid peroxidase and thyroglobulin antibodies were assessed at the beginning and at the end of the study. RESULTS AND DISCUSSION: At baseline there were not differences between the study groups. Although levothyroxine reduced thyrotropin levels, increased free thyroid hormone levels and decreased antibody titers in both study groups, these effects were more pronounced in group A than group B. Only in group A, levothyroxine increased 25-hydroxyvitamin D, decreased hsCRP and improved insulin sensitivity. The impact of levothyroxine on thyrotropin and free thyroid hormones correlated with treatment-induced changes in insulin sensitivity, antibody titers, 25-hydroxyvitamin D and hsCRP. WHAT IS NEW AND CONCLUSION: The present study suggests that the impact of levothyroxine on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity is stronger in women receiving metformin than in women treated with myo-inositol.

The impact of vitamin D on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity in myo-inositol-treated and myo-inositol-naïve women with autoimmune thyroiditis: A pilot study.

WHAT IS KNOWN AND OBJECTIVE: Vitamin D and myo-inositol reduce thyroid antibody titers in subjects with autoimmune thyroiditis. No previous study has investigated interactions between these agents. The aim of the current study was to determine whether the impact of exogenous vitamin D on thyroid autoimmunity and thyroid function in women with Hashimoto's thyroiditis depends on myo-inositol supplementation. METHODS: The study population consisted of three thyroid antibody- and insulin sensitivity-matched groups of women with autoimmune thyroiditis and high-normal or slightly elevated TSH levels. Forty-one women (21 in group A and 20 in group C) had been treated for at least 6 months with myo-inositol (group A), while 21 women (group B) had not received myo-inositol preparations. Over the entire study period (6 months), groups A and C continued treatment with myo-inositol (2 g daily), while groups A and B received exogenous vitamin D (4000 IU daily). Plasma titers of thyroid peroxidase and thyroglobulin antibodies, as well as plasma concentrations of glucose, insulin, TSH, free thyroid hormones, prolactin, and 25-hydroxyvitamin D (25-OH-D) were assessed at entry and 6 months later. Moreover, baseline and follow-up values of the structure parameters of thyroid homeostasis were calculated RESULTS AND DISCUSSION: In groups A and B, vitamin D improved insulin sensitivity and increased 25-OH-D levels. Although follow-up antibody titers in both these groups were lower than baseline ones, the impact of vitamin D on thyroid peroxidase and thyroglobulin antibodies was stronger in group A than in group B. Only in group A, vitamin D decreased TSH levels and increased SPINA-GT. There were no differences between baseline and follow-up free values of glucose, thyroid hormones, prolactin, Jostel's index, and SPINA-GD. The impact of vitamin D treatment on antibody titers correlated with treatment-induced changes in 25-OH-D levels and the degree of improvement in insulin sensitivity. In group C, glucose homeostasis markers, antibody titers and hormone levels remained at a similar level throughout the study period. WHAT IS NEW AND CONCLUSION: The obtained results suggest that the impact of vitamin D on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity in subjects with autoimmune thyroiditis is more pronounced if they receive myo-inositol.

Myo-Inositol Enhances the Inhibitory Effect of Metformin on Gonadotropin Levels in Postmenopausal Women.

OBJECTIVES: Metformin decreased circulating levels of anterior pituitary hormones and its effect on thyrotropin concentration was found to be stronger in individuals receiving myo-inositol. Phospholipids containing inositols are precursors of second messengers of several hormones, including gonadotropins and insulin. The aim of the current study was to investigate whether the concomitant use of myo-inositol changes the effect of metformin on gonadotropin levels. DESIGN: A prospective observational study. PARTICIPANTS/MATERIALS, SETTING, AND METHODS: This study, conducted at a university-affiliated medical center, included two groups of postmenopausal women with prediabetes, matched for age, FSH and LH levels, and insulin sensitivity: women taking myo-inositol preparations for at least 6 months (group A, n = 23) and women not receiving inositol preparations (group B, n = 23). All participants were treated with metformin (850 mg twice daily) for the following 6 months. At the beginning and at the end of the study, we assessed plasma glucose, insulin, FSH, LH, thyrotropin, prolactin, adrenocorticotropic hormone, insulin-like growth factor-1, estradiol, and glycated hemoglobin. RESULTS: The impact of metformin on glucose levels, the homeostatic model assessment 1 of insulin resistance ratio, and glycated hemoglobin was more pronounced in group A than in group B. Metformin administered with myo-inositol reduced both FSH and LH. No significant changes in gonadotropin levels were observed in women receiving only metformin. The impact on FSH and LH levels correlated with their baseline concentrations and with the degree of improvement in insulin sensitivity. Levels of the remaining hormones did not change throughout the study. LIMITATIONS: The most important limitation of the study is a relatively small number of participants. Moreover, the study protocol does not allow to conclude whether similar effects are observed in premenopausal women. CONCLUSIONS: Myo-inositol may enhance the inhibitory effect of metformin on gonadotropin production in postmenopausal women.

Exenatide prevents statin-related LDL receptor increase and improves insulin secretion in pancreatic beta cells (1.1E7) in a protein kinase A-dependent manner.

Statins are primary drugs in the treatment of hyperlipidemias. This group of drugs is known for its beneficial pleiotropic effects (e.g., reduction of inflammatory state). However, a growing body of evidence suggests its diabetogenic properties. The culpable mechanism is not completely understood and might be related to the damage to pancreatic beta cells. Therefore, we conceived an in vitro study to explore the impact of atorvastatin on pancreatic islet beta cells line (1.1.E7). We evaluated the influence on viability, insulin, low-density lipoprotein (LDL) receptor, and proprotein convertase subtilisin/kexin type 9 (PCSK9) expression. A significant drop in mRNA for proinsulin and insulin expression was noted. Concurrently, a rise in LDL receptor at the protein level in cells exposed to atorvastatin was noted. Further experiments have shown that exenatide - belonging to glucagon-like peptide 1 (GLP-1) analogs that are used in a treatment of diabetes and known for its weight reducing properties - can alleviate the observed alterations. In this case, the mechanism of action of exenatide was dependent on a protein kinase A pathway. In conclusion, our results support the hypothesis that statin may have diabetogenic properties, which according to our study is related to reduced insulin expression. The concomitant use of GLP-1 receptor agonist seemed to successfully revert insulin expression.

Plasma Concentrations of New Biochemical Markers of Atherosclerosis in Patients with Dyslipidemia-A Pilot Study.

Background and Objectives: The process of atherosclerotic plaque formation and its destabilisation is a process in which many proteins and cytokines are involved. Examples of such proteins are osteopontin (OPN), osteoprotegerin (OPG), metalloproteinases (MMPs) and myeloperoxidase (MPO). The aim of our study is to compare the concentrations of the above-mentioned markers in the plasma of patients with the confirmed presence of rupture plaque in comparison with the plasma of healthy people. Materials and Methods: The study included people suffering from dyslipidemia in whom the presence of unstable atherosclerotic plaque was confirmed by ultrasound. The concentrations of OPN, OPG, MPO, metalloproteinase 2 (MMP-2), and metalloproteinase 9 (MMP-9) in the plasma of these people were determined and compared with the concentrations of these proteins in the plasma of healthy people. Results: Levels of MMP-2, MMP-9 (p < 0.001), OPN, and OPG (p < 0.05) were statistically significantly lower in the group of healthy people than in the study group. Differences in MPO concentration were not statistically significant (p = 0.073). Conclusions: In the plasma of people with confirmed presence of rupture plaque, the concentrations of OPN, OPG, and MMPs are higher compared to the group of healthy people, which may suggest the use of these proteins as novel markers of the presence of unstable atherosclerotic plaque.