Hsp70 Levels Research Articles

Hypofractionated Radiation Therapy Suppresses Radioresistance in U87 Human Glioma Cells by Inhibiting Yap1 and Hsp90 Proteins.

Radiotherapy plays a vital role in the management of high-grade gliomas. However, the radio resistance of glioma cells limits the effect of radiation and drives recurrence inside the irradiated tumor volume leading to poor outcomes for patients. High-grade glioma cell radioresistance significantly contributes to radiotherapy failure, highlighting the importance of identifying predictive biomarkers for radioresistance. An increasing body of evidence complies with the Yes Associated Protein 1 (Yap-1) and heat shock protein 90 (Hsp90) as biomarkers for radioresistance in glioma cells. A number of studies suggest the potential of radioresistance-associated factors as biomarkers and/ or novel therapeutic targets in glioma cells. Thus, it is essential for glioblastoma patients to identify robust druggable targets involved in radioresistance, optimizing irradiation protocol, and understanding their underlying molecular mechanisms. Therefore, in the present study, we hypothesized that hypofractionated Gamma Knife radiation therapy (HF-GKRT) could target Yap-1 and Hsp90 and downregulate the mechanism of radioresistance in high-grade glioma cells. For this purpose, expression levels of radioresistance markers Yap-1 and Hsp90 were evaluated after treatment with HF-GKRT, and this was compared with single fraction Gamma Knife radiation therapy (SF-GKRT) in U87MG primary human glioblastoma cell line model. This would help design a novel radiation therapy regimen for glioblastoma patients by reducing the risk of radioresistance.

The regulation of ovarian degeneration in Pampus argenteus by heat shock protein genes under low-temperature stress.

Temperature is a crucial environmental factor that significantly impacts the growth, development, metabolism, and physiological functions of fish. To study the effects of low-temperature on the gonadal development of silver pomfret (Pampus argenteus), a cold period by gradually lowering the water temperature from 18°C to 9°C was simulated. The results showed that hsp70, hsp90a, and hsp90b were widely expressed in the tissues of P. argenteus, with hsp70 primarily expressed in the pituitary, hsp90a and hsp90b mainly expressed in the lateral. The hsps were involved in the development process of P. argenteus from 1 to 27 days post-hatching (dph). The expression levels of hsp70 and hsp90b were highest at 17 dph, while the levels of hsp90a were at 25 dph. Under the condition of 9°C, regressed oocyte were observed in the ovaries, the oocyte diameter significantly decreased, and the ovaries degenerated 100% after low-temperature stress. The expression levels of hsps in the ovaries were significantly higher than in the control group, while the expression levels in the testes were significantly lower than in the control group. Taken together, hsps may regulate the ovarian degeneration under low-temperature stress. Male fish rapidly completed meiosis and maintained the testes in the prophase of meiosis to resist the low-temperature stress.

Effect of phosphorylated HSP27 on the proliferation and metastasis of nasopharyngeal carcinoma and its mechanism

Objective:To investigate the effect of phosphorylated HSP27 on the proliferation and metastasis of nasopharyngeal carcinoma and its molecular mechanism. Methods:①Western blot assay was used to detect the expression levels of HSP27 and p-HSP27 in CNE1 and CNE2 cells of nasopharyngeal carcinoma. Inhibited the phosphorylation of HSP27, Transwell assay detected the metastasis ability of nasopharyngeal carcinoma cells. ②Nasopharyngeal carcinoma cell lines（CNE2-OE1 and CNE2-OE2） overexpressing phosphorylated and dephosphorylated mutants of HSP27 were synthesized, empty vector transfected CNE2 cells（CNE2-NC） were used as controls. The proliferation ability of the three groups of cells was detected by CCK8, and the expression levels of CyclinD1, Bax and Bcl-2 were detected by Western blot. Transwell was used to detect the migration and invasion ability of cells, and Western blot was used to detect the expression levels of E-cadherin, Vimentin, MMP2 and MMP9. Results:The expression level of HSP27 in CNE2 was higher than that of CNE1 cells, while the expression level of p-HSP27 was opposite. After inhibition of HSP27 phosphorylation, the invasion and migration ability of CNE1 cells decreased significantly, with no significant change in CNE2 cells. Compared with CNE2-NC, the growth rate of CNE2-OE1 decreased, and the growth rate of CNE2-OE2 increased. The expression level of CyclinD1 was down-regulated in CNE2-OE1 and higher in CNE2-OE2. The expression level of Bax in CNE2-OE1 was increased, while the expression of Bcl-2 was decreased. There was no significant change in the expression of Bax and Bcl-2 in CNE2-OE2. Compared with CNE2-NC, the migration ability of CNE2-OE1 was enhanced and the invasion ability was weakened, while the migration ability of CNE2-OE2 was weakened and the invasion ability was enhanced. There was no significant difference in the expression levels of E-cadherin was decreased in CNE2-OE1 and increased in CNE2-OE2. There was no significant difference in the expression levels of Vimentin among the three groups. The expression levels of MMP2 and MMP9 were up-regulated in CNE2-OE2, and slightly down-regulated in CNE2-OE1. Conclusion:HSP27 and p-HSP27 were differentially expressed in different nasopharyngeal carcinoma cells, and the metastasis ability of nasopharyngeal carcinoma was not only related to the expression level of HSP27, but also related to the level of p-HSP27. The p-HSP27 inhibited CNE 2 cell proliferation and promoted their apoptosis. As p-HSP27 plays different roles in different stages of nasopharyngeal carcinoma metastasis, it can increase the migration ability of CNE2 cells and reduce its invasion ability. p-HSP27 may induce EMT changes in CNE2 by down-regulating E-cadherin, thus promoting CNE2 migration, and may inhibit CNE2 invasion by down-regulating MMPs expression.

Extracellular Hsp70 and Circulating Endometriotic Cells as Novel Biomarkers for Endometriosis.

Stress-inducible heat shock protein 70 (Hsp70), which functions as a molecular chaperone and is frequently overexpressed in different cancer cell types, is present on the cell surface of tumor cells and is actively released into the circulation in free and extracellular lipid vesicle-associated forms. Since the exact pathomechanism of endometriosis has not yet been elucidated (although it has been associated with the development of endometrial and ovarian cancer), we asked whether extracellular Hsp70 and circulating endometriotic cells (CECs) reflect the presence and development of endometriosis. Therefore, circulating levels of free and lipid microvesicle-associated Hsp70 were measured using the Hsp70-exo ELISA, and the presence of circulating CECs in the peripheral blood of patients with endometriosis was determined using membrane Hsp70 (mHsp70) and EpCAM monoclonal antibody (mAb)-based bead isolation approaches. Isolated CECs were further characterized by immunofluorescence using reagents directed against cytokeratin (epithelial marker), CD45 (leukocyte marker), CD105/CD44 (mesenchymal stemness markers) and by comparative RNA analysis. Similar to the situation in patients with cancer, the levels of circulating Hsp70 were elevated in the blood of patients with histologically proven endometriosis compared to a healthy control cohort, with significantly elevated Hsp70 levels in endometriosis patients with lesions outside the uterine cavity. Moreover, CECs could be isolated using the cmHsp70.1 mAb-based, and to a lesser extent EpCAM mAb-based, bead approach in all patients with endometriosis, with the highest counts obtained using the mHsp70-targeting procedure in patients with extra-uterine involvement. The longevity in cell culture and the expression of the cytokeratins CD105 and CD44, together with differentially expressed genes related to epithelial-to-mesenchymal transition (EMT), revealed similarities between mHsp70-expressing CECs and circulating tumor cells (CTCs) and suggest a mesenchymal stem cell origin. These findings support the involvement of mHsp70-positive stem cell-like cells in the development of endometriotic lesions. In summary, elevated levels of Hsp70 and CECs in the circulation could serve as liquid biopsy markers for endometriosis with extra-uterine involvement and help to elucidate the underlying pathomechanism of the disease.

Glucose and glutamine drive hepatitis E virus replication.

Viruses have undergone evolutionary adaptations to tune their utilization of carbon sources, enabling them to extract specific cellular substrates necessary for their replication. The lack of a reliable cell culture system and a small-animal model has hampered our understanding of the molecular mechanism of replication of hepatitis E virus (HEV) genotype 1. Our recent identification of a replicative ensemble of mutant HEV RNA libraries has allowed us to study the metabolic prerequisites for HEV replication. Initial assessments revealed increased glucose and glutamine utilization during HEV replication. Inhibition of glycolysis and glycolysis + glutaminolysis reduced the levels of HEV replication to similar levels. An integrated analysis of protein-metabolite pathways suggests that HEV replication markedly alters glycolysis, the TCA cycle, and glutamine-associated metabolic pathways. Cells supporting HEV replication showed a requirement for fructose-6-phosphate and glutamine utilization through the hexosamine biosynthetic pathway (HBP), stimulating HSP70 expression to facilitate virus replication. Observations of mannose utilization and glutamine dependence suggest a crucial role of the HBP in supporting HEV replication. Inhibition of glycolysis and HSP70 activity or knockdown of glutamine fructose-6-phosphate amidotransferase expression led to a substantial reduction in HEV RNA and ORF2 expression accompanied by a significant decrease in HSP70 levels. This study demonstrates that glucose and glutamine play critical roles in facilitating HEV replication.

Cloning and functional analysis of heat shock protein Hsp70 from Sclerotinia sclerotiorum

To clarify the roles of the heat shock protein gene Hsp70 in the sclerotial formation and pathogenicity of Sclerotinia sclerotiorum, we employed reverse transcription PCR (RT-PCR) to clone Hsp70 from S. sclerotiorum and performed sequence analysis. Quantitative real-time PCR (qRT-PCR) was employed to determine the relative expression levels of Hsp70 at different growth stages and under the stress induced by cyclic adenosine monophosphate (cAMP) and low and high temperatures. The thermal stability of Hsp70 was measured. The Agrobacterium-mediated method was employed to construct the Hsp70-silenced strain. The pathogenicity and fungicide resistance of strains were tested by inoculation in detached rapeseed leaves and cultivation in the media containing procymidone and thiophanate-methyl, respectively. The results showed that the cloned Hsp70 had a total length of 1 890 bp and close relationship with the Hsp70 gene of Ciborinia. Hsp70 showcased the highest expression level in sclerotia, which was more than 30 times higher than that in hyphae. The cAMP stress significantly induced the expression of Hsp70. The expression level of Hsp70 showed an increasing-decreasing-increasing trend at 40 ℃ and no significant change at 4 ℃. Recombinant strain with high expression of Hsp70 showed good thermal stability. The Hsp70-silenced transformant did not form sclerotia, with decreased pathogenicity and fungicide resistance. This study reveals that Hsp70 plays an important role in the sclerotial formation and stress resistance of S. sclerotium, providing reference for further in-depth research on the biological roles of Hsp70 in S. sclerotium.

Heat shock protein 70 promotes the progression of type 2 diabetic nephropathy by inhibiting T-cell immunoglobulin and mucin domain-3 and thereby promoting Th17/Treg imbalance.

Diabetic nephropathy (DN) is the most common complication of diabetes mellitus. We aimed to investigate the role of regulatory T cells (Tregs) and helper T cells 17 (Th17) in the development and progression of DN. A mouse type 2 diabetic nephropathy (T2DN) model was established. Immunohistochemistry was used to detect the expression of HSP70 and Tim-3 in mouse kidney tissues, and western blotting was used to detect the expression levels of HSP70 and Tim-3. PAS staining and Masson's trichrome staining were used to detect the degree of kidney injury. Flow cytometry was used to detect the number of Th17 and Treg cells in blood and kidney tissues. The expression levels of interleukin 17 (IL-17) and interleukin 10 (IL-10) in the serum were measured via ELISA. The expression of HSP70 was significantly increased while the expression of Tim-3 was significantly decreased in the kidneys of mice in the T2DN group compared with those in the control (NC) group. Additionally, the inhibition of HSP70 upregulated the expression of Tim-3 in T2DN mice. The Th17/Treg ratio was significantly greater in the blood and kidneys of the mice in the T2DN group than in those of the NC group, the expression of serum IL-17 was increased, and the expression of IL-10 was decreased. Increased HSP70 inhibits Tim-3 expression in T2DN mouse kidney tissues, and subsequently causes a Th17/Treg imbalance and an inflammatory response, ultimately leading to kidney injury. The inhibition of HSP70 may alleviate the progression of T2DN.

Exploring the Gene Expression and Plasma Protein Levels of HSP90, HSP60, and GDNF in Multiple Sclerosis Patients and Healthy Controls.

Multiple sclerosis (MS) is a chronic neurodegenerative disease characterized by immune-mediated inflammation and neurodegeneration in the central nervous system (CNS). In this study; we aimed to investigate the gene expression and plasma protein levels of three neuroprotective genes-heat shock proteins (HSP90 and HSP60) and glial cell line-derived neurotrophic factor (GDNF)-in MS patients compared to healthy controls. Forty patients with relapsing-remitting MS and 40 healthy volunteers participated in this study. Gene expression was measured using reverse transcription quantitative real-time PCR, and protein levels were assessed via ELISA. The results showed a significant increase in HSP90 (1.7-fold) and HSP60 (2-fold) gene expression in MS patients compared to controls, along with corresponding increases in protein levels (1.5-fold for both HSP90 and HSP60). In contrast, GDNF gene expression and protein levels were significantly reduced in MS patients, with a 7-fold decrease in gene expression and a 1.6-fold reduction in protein levels. Notably, a non-linear relationship between GDNF gene expression and protein concentration was observed in MS patients, suggesting complex regulatory mechanisms influencing GDNF in the disease. The upregulation of HSP90 and HSP60 in MS highlights their roles in immune regulation and stress responses, while the reduction in GDNF indicates impaired neuroprotection. These findings suggest that HSP90, HSP60, and GDNF could serve as biomarkers for disease progression and as potential therapeutic targets in MS, offering promising avenues for future research and treatment development.

Effect of Benzyl Alcohol on Main Defense System Components of Galleria mellonella (Lepidoptera).

Benzyl alcohol (E1519) is an aromatic alcohol used in the pharmaceutical and food industry. It is used to protect food products against microorganisms during storage, as a flavoring in the production of chocolate and confectionery products, as an important ingredient in fragrance, and as a preservative in medical products. However, little is known of its effect on insects. The main aim of this study was to determine the influence of benzyl alcohol on the defense systems of the wax moth Galleria mellonella, i.e., its cuticular lipid composition and critical elements of its immune system. A gas chromatography/mass spectrometry (GC/MS) analysis found benzyl alcohol treatment to elicit significant quantitative and qualitative differences in cuticular free fatty acid (FFA) profiles. Our findings indicate that benzyl alcohol treatment increased the levels of HSP70 and HSP90 and decreased those of HSF1, histamine, and cysteinyl leukotriene. Benzyl alcohol application also increased dismutase level in the hemolymph and lowered those of catalase and 8-OHdG. The treatment also had negative effects on G. mellonella hemocytes and a Sf9 cell line in vitro: 48-h treatment resulted in morphological changes, with the remaining cells being clearly spindle-shaped with numerous granules. The high insecticidal activity of compound and its lack of toxicity towards vertebrates suggest it could be an effective insecticide.

Promising predictors of diabetic peripheral neuropathy in children and adolescents with type 1 diabetes mellitus

BackgroundDiabetic peripheral neuropathy (DPN) in children and adolescents with type 1 diabetes mellitus (T1DM) is a growing issue, with controversial data in the terms of prevalence and evaluation timelines. Currently, there are no clear standards for its early detection. Therefore, our aim was to assess the contribution of the Michigan neuropathy screening instrument (MNSI), lipid profile, serum neuron specific enolase (NSE), and serum heat shock protein 27 (HSP 27) to the prediction of DPN in children and adolescents with T1DM.MethodsIn this case-control study, fifty children diagnosed with T1DM for at least five years were enrolled and evaluated through complete neurological examination, MNSI, and nerve conduction study (NCS). Additionally, HbA1c, lipid profile, serum NSE, and serum HSP 27 levels were measured for patients and controls.ResultsThe prevalence of DPN in our study was 24% by NCS, and electrophysiological changes showed a statistically significant lower conduction velocity for the posterior tibial and sural nerves, as well as a prolonged latency period for the common peroneal and sural nerves in neuropathic patients. In these patients, older age, earlier age of diabetes onset, longer disease duration, higher total cholesterol, triglycerides, low density lipoprotein cholesterol, HbA1c, serum NSE, and HSP27 levels were observed. The MNSI examination score ≥ 1.5 cutoff point had an area under the curve (AUC) of 0.955, with 75% sensitivity and 94.74% specificity, according to receiver operating characteristic curve analysis. However, the questionnaire’s cutoff point of ≥ 5 had an AUC of 0.720, 75% sensitivity, and 63% specificity, with improved overall instrument performance when combining both scores. Regarding blood biomarkers, serum NSE had greater sensitivity and specificity in discriminating neuropathic patients than HSP27 (92% and 74% versus 75% and 71%, respectively). Regression analysis revealed a substantial dependency for MNSI and serum NSE in predicting DPN in patients.ConclusionsDespite limited research in pediatrics, MNSI and serum NSE are promising predictive tools for DPN in children and adolescents with T1DM, even when they are asymptomatic. Poor glycemic control and lipid profile changes may play a critical role in the development of DPN in these patients, despite conflicting results in various studies.

Sirtuin 7 ameliorates cuproptosis, myocardial remodeling and heart dysfunction in hypertension through the modulation of YAP/ATP7A signaling.

Myocardial fibrosis is a typical pathological manifestation of hypertension. However, the exact role of sirtuin 7 (SIRT7) in myocardial remodeling remains largely unclear. Here, spontaneously hypertensive rats (SHRs) and angiotensin (Ang) II-induced hypertensive mice were pretreated with recombinant adeno-associated virus (rAAV)-SIRT7, copper chelator tetrathiomolybdate (TTM) or copper ionophore elesclomol, respectively. Compared with normotensive controls, reduced SIRT7 expression and augmented cuproptosis were observed in hearts of hypertensive rats and mice with decreased FDX1 levels and increased HSP70 levels. Notably, intervention with rAAV-SIRT7 and TTM strikingly prevented DLAT oligomers aggregation, and elevated ATP7A and TOM20 expressions, contributing to the alleviation of cuproptosis, mitochondrial injury, myocardial remodeling and heart dysfunction in spontaneously hypertensive rats and Ang II-induced hypertensive mice. In cultured rat primary cardiac fibroblasts (CFs), rhSIRT7 alleviated CuCl2, Ang II or elesclomol-induced cuproptosis and fibroblast activation by blunting DLAT oligomers accumulation and downregulating α-SMA expression. Additionally, conditioned medium from rhSIRT7-pretreated CFs remarkably mitigated cellular hypertrophy and mitochondrial impairments of neonatal rat cardiomyocytes, as well as cell migration and polarization of RAW 264.7 macrophages. Importantly, verteporfin reduced CuCl2-induced cuproptosis, mitochondrial injury and fibrotic activation in CFs. Knockdown of ATP7A with si-ATP7A blocked cellular protective effects of rhSIRT7 and verteporfin in CFs. In conclusion, SIRT7 attenuates cuproptosis, myocardial fibrosis and heart dysfunction in hypertension through the modulation of YAP/ATP7A signaling. Targeting SIRT7 is of vital importance for developing therapeutic strategies in hypertension and hypertensive heart disorders.

Stocking density affects growth, feed utilisation, metabolism, welfare and associated mRNA transcripts in liver and muscle of rainbow trout more pronouncedly than dietary fish meal inclusion level

In aquaculture, stocking density and diet composition are critical factors that influence the performance and welfare of the farmed animal. However, there is limited information on their interactive effects. In this context, applying a 2 × 2 factorial design, we conducted a 12-week feeding trial to evaluate the effect of stocking density (low, LSD: 3.3–15 kg m−3 and high, HSD: 5.8–25 kg m−3; initial-final values) and dietary fish meal content (high, HFM: 30 % and low, LFM: 15 %) on growth, feed utilisation, metabolic oxygen consumption, tissue indices, carcass composition, plasma metabolites, and transcriptional regulation of growth, metabolism and welfare-related biomarker mRNAs in liver and muscle of the juvenile rainbow trout. At the whole-animal level, the HSD group showed significantly higher routine metabolic rate and feed intake indicating higher energy demand; but growth and feed efficiency was lower in HSD than the LSD group. Morpho-anatomically, HSD fish had lower relative gut length and higher intra-peritoneal fat index than LSD fish. Lower plasma free amino acids and glucose levels reiterated high energy expenditure in HSD, and elevated albumin levels indicated potential oxidative stress in the HSD group. Correspondingly, at the transcriptional level, hepatic mRNA levels of antioxidative enzymes (sod, cat, gst, g6pd) and stress-related molecular chaperone hsp90 were up-regulated in HSD; while the transcript abundance of growth-axis markers (ghr, igf1 igf2) and nutrient-sensor mtor were decreased. In muscle, proteolytic pathway components fbx32 and murf1 were upregulated in HSD, and concurrently mtor was also upregulated suggesting higher protein turnover in this group. With respect to the effect of dietary fish meal inclusion levels, LFM showed decrease in growth, hepatic igf2 expression, and lower plasma triglycerides and free amino acid levels than HFM group. However, the sensory appearance of flesh was found to be slightly better in LFM. Significant diet-husbandry interactions were not observed phenotypically, but the mRNA abundance of hepatic markers (ampk1, hsp70, mhc1 and tnfa) linked to energy-sensing, stress and immune response were differentially regulated. Overall, the study shows that high stocking density has a greater degree of impact on fish growth and welfare than reduction in dietary fishmeal inclusion, with limited interactional effects.

Toxic Effects of Imidacloprid, Copper Sulfate, and Their Combinations on Biomolecular and Oxidative/Antioxidant Biomarkers in the Tissues of Oreochromis niloticus.

The wide-ranging use of heavy metals and pesticides worldwide and their irreversible accumulation in aquatic ecosystems is a major concern. As the range of household and agricultural chemicals increases, water pollution is trending from the toxic effects of a single agent to complex agent pollution that threatens aquatic ecosystems. The aim of this study was to investigate the effects of pesticides (imidacloprid, IMI) and metals (copper sulfate, CuSO4) on oxidative stress biomarkers, antioxidant enzymes, and biomolecular parameters. The present study on the individual and combined effects of Oreochromis niloticus copper sulfate (CuSO4; 1ppm), imidacloprid (IMI; 10 and 50ppm), and IMI + CuSO4 (IMI10 + CuSO4, IMI50 + CuSO4) groups for 14days. In this context, oxidative stress/antioxidant markers (SOD, CAT, GST, and GSH) and biomolecular markers including HSP70, 8-OHdG, PC, and TBARS levels were examined in fish liver and kidney tissues, which are detoxification organs. The results indicated that IMI and CuSO4 toxicity alone and in combination altered oxidative stress/antioxidant markers and biomolecular parameters; moreover, 14days of exposure to the combination of CuSO4 and imidacloprid in particular exhibited a synergistic effect and caused oxidative toxicity. These findings highlighted the importance of evaluating mixtures of pesticides and metals and that the results show a remarkably synergistic effect. It can be concluded that these biomarkers are important indicators of physiological changes in living organisms.

Level of Hsp60 in periodontal tissues after photodynamic therapy

Level of Hsp60 in periodontal tissues after photodynamic therapy

Hot and cold exposure triggers distinct transcriptional and behavioral responses in laboratory-inbred pond snails

Animals exhibit remarkable behavioral and molecular adaptations to cope with thermal stressors, which are crucial for survival in variable environments that are exacerbated by climate change. Aquatic poikilotherms like our model organism—the pond snail Lymnaea stagnalis—face significant challenges due to their dependence on external temperatures. Our study provides valuable insights into the different behavioral and molecular responses of lab-inbred snails to cold and heat shock stressors (i.e., 4 °C and 30 °C), particularly in the context of learning and memory formation. We found that while short-term (1 h) cold exposure transiently upregulated the expression levels of HSP70 and HSP40 in the snail’s central ring ganglia, prolonged cold exposure (24 h) resulted in a significant downregulation of LymMIPII and an upregulation of LymMIPR. These data suggest, albeit at the transcriptional level, the existence of a negative feedback loop necessary for sustaining cellular functions when metabolic demands might shift towards conserving energy during prolonged cold exposure. At the behavioral level, we found that, compared to heat shock, cold exposure did not result in a Garcia effect (i.e., a “special form” of conditioned taste aversion). The difference in memory outcomes was associated with changes in the expression levels of selected targets involved in neuronal plasticity and the stress response. While both cold and heat shock upregulated the HSP levels in the snail's central ring ganglia, cold exposure did not affect the expression levels of the neuroplasticity genes LymGRIN1 and LymCREB1, contrasting with heat shock’s neurogenic effects. Overall, this study provides insights into L. stagnalis's adaptive responses to thermal stressors, emphasizing different molecular strategies for coping with heat versus cold challenges in aquatic environments. These findings contribute to our understanding of thermal biology and stress physiology in aquatic organisms, underscoring the importance of molecular mechanisms in shaping species' resilience in dynamic environments.

The Effect of Selenase on Inflammatory and Cytoprotective Markers in Experimental Chronic Generalized Periodontitis

Epidemiological studies in recent decades have revealed a significant increase in the number of patients with periodontal diseases leading to tooth loss. Modern realities require improvement of drug treatment of periodontitis. The antioxidant Selenase, selenium derivative, is an interesting treatment strategy for periodontitis. The study was carried out with the aim to evaluate the healing effectiveness of Selenase in rats with chronic generalized periodontitis (CGP) by its effect on markers of inflammation and cytoprotection. Experimental CGP was modulated in Wistar rats by a calcium-deficient diet with the inclusion of a prooxidant. Selenase (50 mcg/kg) and Mexidol (ethylmethylhydroxypyridine succinate, 250 mg/kg) were administered intragastrically for 30 days. Levels of IL-1β, HIF-1α, HSP70, and TNF-α were determined in the blood after treatment using the enzyme immunoassay method. Experimental CGP was characterized by the development of hyperemia, swelling, and bleeding of the gums; mobility of teeth; and gingival pockets up to 8 mm against the background of increased inflammatory markers (IL-1β, TNF-α), and molecular markers of cytoprotection (HIF-1α, HSP70) in the blood, indicating a homeostatic response of the periodontium in response to inflammation and subsequent hypoxia. Administration of Selenase to rats with CGP produced pronounced healing effects: the reduction in the depth of periodontal pockets by 42.55 %, cessation of bleeding, and disappearance of swelling against the background of a decrease of inflammatory markers: IL-1β – by 44.6 %, and TNF-α – by 65.9 % (p < 0.05). HIF-1α increased by 36.8 %, and HSP70 – by 71.1 % compared to those of the control group, which was not given the treatment (p < 0.05). The results obtained suggest a significant influence of Selenase on HSP70-dependent mechanisms of endogenous cytoprotection. The results of the study found that the use of Selenase in experimental CGP is more effective than Mexidol.

LEVELS OF HEAT SHOCK PROTEIN HSP70 IN NEURONS OF PARIETAL CORTEX AND HIPPOCAMPUS IN RATS WITH VARIOUS STAGES OF CEREBRAL ISCHEMIA

The paper examines the issue of increasing the body’s resistance to oxygen deficiency and energy deficit under cerebral ischemia. Adaptation to these changes is represented by an increased number of heat shock proteins in brain neurons. Their expression increases with a decrease of oxygen level in the blood. The aim of the paper is to evaluate HSP70 level in the brain of rats with various stages of cerebral ischemia. Materials and Methods. The study was conducted on 27 white outbred male rats weighing 267±16 g. The authors used such models as partial cerebral ischemia, step-by-step 90 % blood flow shutdown, one-time 90 % blood flow shutdown, and complete cerebral ischemia. Results. In the 1st subgroup of step-by-step 90 % blood flow shutdown (7 days between dressings) there was an increase in the HSP70 level by 25 % in the parietal cortex (p<0.05) compared with the control. However, its concentration in the hippocampus did not change (p>0.05). In the 2nd and 3rd subgroups of step-by-step 90 % blood flow shutdown (3 days and 1 day between dressings), the HSP70 level did not change in any of the studied areas (p>0.05) compared with the control. Compared with the 1st subgroup, in the 2nd subgroup HSP70 level in the parietal cortex was lower by 26 % (p<0.05) and in the hippocampus by 20 % (p<0.05), in the 3rd subgroup it was lower by 30 % (p<0.05) and by 23 % (p<0.05), respectively. No differences in HSP70 levels were found between the 2nd and 3rd subgroups (p>0.05). In the group of one-time 90 % blood flow shutdown, the HSP70 level decreased by 29 % in the parietal cortex (p<0.05) and by 18 % in the hippocampus (p<0.05) compared with the control. In group of one-time 90 % blood flow shutdown, the HSP70 level did not differ from those in the 2nd and 3rd subgroups of step-by-step 90 % blood flow shutdown in the hippocampus. In the parietal cortex, the HSP70 level in the 2nd subgroup was 28 % higher (p<0.05), and in the 3rd subgroup by 23 % higher (p<0.05) compared with the group of one-time 90 % blood flow shutdown. In total cerebral ischemia, the most significant decrease in HSP70 level was observed compared to the control: by 35 % in the parietal cortex (p<0.05) and by 36 % in the hippocampus (p<0.05). Conclusion. Thus, in the 1st subgroup with the maximum interval between dressings, the HSP70 level increased, indicating the activation of compensation mechanisms during hypoxia by protecting proteins from premature proteolytic breakdown and promoting the correct polypeptide folding into a tertiary structure.

New Mitochondria-Targeted Fisetin Derivative Compromises Mitophagy and Limits Survival of Drug-Induced Senescent Breast Cancer Cells.

Mitochondria are considered as promising targets for cancer treatment. In the present study, triphenyl phosphonium cationic group-conjugated fisetin (mito-fisetin) was synthesized, and its anticancer activity was investigated in several cellular models of estrogen receptor (ER)-positive breast cancer in vitro and in vivo in proliferating and tamoxifen-promoted senescent states. Mito-fisetin, when used at low micromolar concentrations, stimulated the dissipation of mitochondrial membrane potential and oxidative stress, and affected mitochondrial function, resulting in apoptosis induction in senescent breast cancer cells. Mito-fisetin-mediated cytotoxicity was due to increased levels of phosphorylated AMPK, decreased levels of AKT and HSP90, and impaired mitophagic response, as judged by the analysis of the markers of mitophagosome formation. Senescent breast cancer cells were found to be more sensitive to mito-fisetin treatment than proliferating ones. We postulate that mitochondrial targeting in the case of fisetin may be considered as a promising anticancer and senotherapeutic strategy to eliminate drug-resistant senescent breast cancer cells.

Probiotic strategies for mitigating heat stress effects on broiler chicken performance.

The primary objective of this study was to evaluate the effects of liquid (Fructose-added lactic acid bacteria, F-LAB) and commercial (Commercial LAB, C-LAB) probiotics sourced from Rye-Grass Lactic Acid Bacteria (LAB) on broiler chickens experiencing heat stress (HS). The research involved 240 broiler chicks, divided into six groups: control, F-LAB, C-LAB (raised at 24°C), HS, F-LAB/HS, and C-LAB/HS (exposed to 5-7h of 34-36°C daily). The study followed a randomized complete block design, with each group consisting of 40 chicks. F-LAB and HS/F-LAB groups received a natural probiotic added to their drinking water at a rate of 0.5ml/L, while C-LAB and HS/C-LAB groups were supplemented with a commercial probiotic at the same dosage. Control and HS groups received no probiotic supplementation. The duration of the study was 42days, with data collected on growth performance, feed intake, feed conversion ratio, and health parameters. Statistical analyses were performed using ANOVA, and significant differences between groups were determined using post hoc tests. The results revealed that without probiotic supplementation, heat stress led to a decrease in body weight gain, T3 levels, citrulline, and growth hormone levels, along with an increase in the feed conversion ratio, serum corticosterone, HSP70, ALT, AST, and leptin levels (p < 0.05 for all). Heat stress also adversely affected cecal microbiota, reducing lactic acid bacteria count (LABC) while increasing Escherichia coli and coliform bacteria (CBC) counts. However, in the groups receiving probiotic supplementation under heat stress (F-LAB/HS and C-LAB/HS), these effects were alleviated (p < 0.05 for all). Particularly noteworthy was the observation that broiler chickens supplemented with natural lactic acid bacteria (F-LAB) exhibited greater resilience to heat stress compared to those receiving the commercial probiotic, as evidenced by improvements in growth, liver function, hormonal balance, intestinal health, and cecal microbiome ecology (p < 0.05). These findings suggest that the supplementation of naturally sourced probiotics (F-LAB) may positively impact the intestinal health of broiler chickens exposed to heat stress, potentially supporting growth and health parameters.

Flow cytometric analysis of the interaction of monoclonal antibodies to various epitopes of the HSP70 molecule with intracellular and membrane-associated forms of this protein

Currently, a large amount of data has demonstrated that many types of tumor cells, in contrast to their non-transformed forms, are characterized by the translocation of intracellular heat shock proteins 70 kDa (HSP70) to the surface of the plasma membrane. This made it possible to classify HSP70 exposed on the cell surface as a tumor-associated antigen and was the basis for searching the opportunities for the practical use of this phenomenon in clinical oncology. A significant argument in favor of the prospects of such studies was the discovered ability of HSP70, present on the surface of target cells, to enhance the cytotoxic activity of NK cells. In this regard, the work of many research groups is devoted to developing approaches to increasing the level of membrane-associated HSP70 in tumor tissues. At the same time, given the presence of such proteins on the surface of many types of tumor cells, the use of monoclonal antibodies that interact with HSP70 molecules for antitumor therapy can be considered as one of the promising approaches. It is well known that antibody preparations that selectively interact with cancer cells can be used for targeted antitumor immunotherapy. Previously, we obtained a panel of six B cell hybridomas producing monoclonal antibodies to the inducible and constitutive forms of human HSP70, directed to various epitopes of this molecule. It is significant that three varieties of hybridomas produced antibodies with specificity for binding sites on the C-terminal domain of the HSP70 molecule, and the second trio of monoclonal antibodies were specific to epitopes on the N-terminal domain of HSP70, while almost all known commercial antibodies interact only with C-terminal fragments of HSP70. In this work, we conducted a comparative study of the binding of the obtained antibodies to these proteins localized in different types of cells, both in the intracellular space and on the cell surface.The results obtained allow us to consider the identified varieties of monoclonal antibodies that most effectively recognize surface HSP70 as a promising basis for the creation of new drugs for antitumor immunotherapy.