Induction Of Heat Shock Proteins Research Articles

Hyperthermia and targeting heat shock proteins: innovative approaches for neurodegenerative disorders and Long COVID

Neurodegenerative diseases (NDs) and Long COVID represent critical and growing global health challenges, characterized by complex pathophysiological mechanisms including neuronal deterioration, protein misfolding, and persistent neuroinflammation. The emergence of innovative therapeutic approaches, such as whole-body hyperthermia (WBH), offers promising potential to modulate underlying pathophysiological mechanisms in NDs and related conditions like Long COVID. WBH, particularly in fever-range, enhances mitochondrial function, induces heat shock proteins (HSPs), and modulates neuroinflammation—benefits that pharmacological treatments often struggle to replicate. HSPs such as HSP70 and HSP90 play pivotal roles in protein folding, aggregation prevention, and cellular protection, directly targeting pathological processes seen in NDs like Alzheimer's, Parkinson's, and Huntington's disease. Preliminary findings also suggest WBH's potential to alleviate neurological symptoms in Long COVID, where persistent neuroinflammation and serotonin dysregulation are prominent. Despite the absence of robust clinical trials, the therapeutic implications of WBH extend to immune modulation and the restoration of disrupted physiological pathways. However, the dual nature of hyperthermia's effects—balancing pro-inflammatory and anti-inflammatory responses—emphasizes the need for dose-controlled applications and stringent patient monitoring to minimize risks in vulnerable populations. While WBH shows potential interest, significant challenges remain. These include individual variability in response, limited accessibility to advanced hyperthermia technologies, and the need for standardized clinical protocols. Future research must focus on targeted clinical trials, biomarker identification, and personalized treatment strategies to optimize WBH's efficacy in NDs and Long COVID. The integration of WBH into therapeutic paradigms could mark a transformative step in addressing these complex conditions.

HSP mRNA sequences and theirexpression under different thermal oscillation patterns and heat stress in two populations of Nodipecten subnodosus.

Understanding the molecular mechanisms underlying thermal acclimation and heat shock responsesin marine ectotherms is critical for assessing their adaptive capacity in the context of climate change and climate extremes. This study examines the expression dynamics of heat shock proteins (HSPs) in the scallop Nodipecten subnodosus, shedding light on their role in thermal adaptation. Our analysis revealed the presence of several conserved functional signatures in N. subnodosus HSPs deduced amino acid sequences. Comparative gene expression profiling between two populations of N. subnodosus, maintained for 15 days under constant and oscillatory thermal regimes and then exposed to acute heat stress, revealed conserved adaptive traits. The heat-inducible nature of N. subnodosus HSP70 (HSPA8) gene expression highlights its potential as a stress marker, in contrast to its human homolog, which is constitutively expressed. Furthermore, the identification of HSP90 (HSPC3) and its overexpression during acute heat stress underscores its critical role in initiating a protective stress response. Population-specific responses in the magnitude of gene expression were observed; however, both populations exhibited similar overall patterns of HSP induction, suggesting a shared adaptive response mechanism. This study also elucidated the diversity and expansion of members of the HSP70 family members, specifically the HSPA12 subfamily, in N. subnodosus. This characteristic, previously observed in other bivalves, underscores the role of HSPA12 in environmental adaptation, providing molecular plasticity to withstand varying environmental pressures. These findings offer valuable insights into the molecular basis of thermal adaptation in N. subnodosus, highlighting the importance of HSPs in coping with environmental stochasticity under climate change scenarios.

Differences in gene expression between high and low tolerance rainbow trout (Oncorhynchus mykiss) to acute thermal stress.

Understanding the mechanisms that underlie the adaptive response of ectotherms to rising temperatures is key to mitigate the effects of climate change. We assessed the molecular and physiological processes that differentiate between rainbow trout (Oncorhynchus mykiss) with high and low tolerance to acute thermal stress. To achieve our goal, we used a critical thermal maximum trial in two strains of rainbow trout to elicit loss of equilibrium responses to identify high and low tolerance fish. We then compared the hepatic transcriptome profiles of high and low tolerance fish relative to untreated controls common to both strains to uncover patterns of differential gene expression and to gain a broad perspective on the interacting gene pathways and functional processes involved. We observed some of the classic responses to increased temperature (e.g., induction of heat shock proteins) but these responses were not the defining factors that differentiated high and low tolerance fish. Instead, high tolerance fish appeared to suppress growth-related functions, enhance certain autophagy components, better regulate neurodegenerative processes, and enhance stress-related protein synthesis, specifically spliceosomal complex activities, mRNA regulation, and protein processing through post-translational processes, relative to low tolerance fish. In contrast, low tolerance fish had higher transcript diversity and demonstrated elevated developmental, cytoskeletal, and morphogenic, as well as lipid and carbohydrate metabolic processes, relative to high tolerance fish. Our results suggest that high tolerance fish engaged in processes that supported the prevention of further damage by enhancing repair pathways, whereas low tolerance fish were more focused on replacing damaged cells and their structures.

Heat acclimation mediates cellular protection via HSP70 stabilization of HIF-1α protein in extreme environments.

Heat acclimation (HA) is an evolutionarily conserved trait that enhances tolerance to novel stressors by inducing heat shock proteins (HSPs). However, the molecular mechanisms underlying this phenomenon remain elusive. In this study, we established a HA mouse model through intermittent heat stimulation. Subsequently, this model was evaluated using an array of physiological and histological assessments. In vitro, HA cell model with mouse brain microvascular endothelial cells (bEnd.3) was established and analyzed for cell viability and apoptosis markers. We investigated HA-mediated heat and hypoxia tolerance mechanisms using HIF-1α and HSP70 inhibitors and siRNA. Our results demonstrated that HA enhances the tolerance of bEnd.3 cells and mice to both heat and hypoxia, Mechanistically, HA upregulated the expression of HIF-1α and HSP70. However, inhibition of HIF-1α or HSP70 partially attenuated HA-induced tolerance to heat and hypoxia. Additionally, HA significantly decreased the ubiquitination levels of HIF-1α, whereas inhibition of HSP70 increased its ubiquitination. HA also substantially enhanced the interaction between HIF-1α and HSP70. In conclusion, our findings indicate that HA enhances tolerance to heat and hypoxia by stabilizing HIF-1α through increased interaction with HSP70. This discovery elucidates a novel mechanism of cellular protection conferred by HA and provides new strategies and potential targets for human adaptation to extreme environments.

MTOR signalling controls protein aggregation during heat stress and cellular aging in a translation- and Hsf1-independent manner.

The mTOR (mechanistic target of rapamycin) signaling pathway appears central to the aging process as genetic or pharmacological inhibition of mTOR extends lifespan in most eukaryotes tested. While the regulation of protein synthesis by mTOR has been studied in great detail, its impact on protein misfolding and aggregation during stress and aging is less explored. In this study, we identified the mTOR signaling pathway and the linked SEA complex as central nodes of protein aggregation during heat stress and cellular aging, using Saccharomyces cerevisiae as a model organism. Based on a synthetic genetic array (SGA) screen, we found that reduced mTOR activity, achieved through deletion of TCO89, an mTORC1 subunit, almost completely prevents protein aggregation during heat stress and aging without reducing global translation rates and independently of an Hsf1-dependent stress response. Conversely, increased mTOR activity, achieved through deletion of NPR3, a SEA complex subunit, exacerbates protein aggregation, but not by over-activating translation. In summary, our work demonstrates that mTOR signaling is a central contributor to age-associated and heat shock-induced protein aggregation and that this is unlinked to quantitatively discernable effects on translation and Hsf1.

Species-specific differences in acetaminophen hepatotoxicity depend on HSP70 expression level.

Acetaminophen (N-Acetyl-p-aminophenol: APAP) is one of the most commonly used analgesic/antipyretic drugs with proven safety at therapeutic doses, however, over-dosage causes dose-dependent liver damage, leading to acute liver failure in severe cases. The level of APAP-induced liver injury has been known to vary among animal species, and APAP concentrations that induce cell death have been investigated using primary cultured cells. We constructed in vitro model of APAP-induced hepatotoxicity using mouse, rat, and human hepatoma cell lines to investigate species differences in the APAP-induced cytotoxicity by monitoring cell death as a marker. The EC50 for each cell line was Hepa1-6 (mouse) < H-4-II-E (rat) < Hep3B (human), while the expression of heat shock protein 70 (HSP70), which was a typical molecular chaperone, positively correlated with the EC50 of each cell. Heat shock treatment, which caused activation of heat shock factor 1 (HSF1) followed by significant induction of HSP70, partially suppressed APAP-induced cell death in Hepa1-6 and H-4-II-E. Moreover, HSP70 or HSF1 siRNA treatment in Hep3B enhanced APAP-induced cell death. These results suggest that APAP-induced cell death in hepatoma cell lines may be partly mediated by protein denaturation and that the expression level of HSP70 has an inhibitory effect.

Phototactic/Photosynthetic/Magnetic-Powered Chlamydomonas Reinhardtii-Metal-Organic Frameworks Micro/Nanomotors for Intelligent Thrombolytic Management and Ischemia Alleviation.

Thrombosis presents a critical health threat globally, with high mortality and incidence rates. Clinical treatment faces challenges such as low thrombolytic agent bioavailability, thrombosis recurrence, ischemic hypoxia damage, and neural degeneration. This study developed biocompatible Chlamydomonas Reinhardtii micromotors (CHL) with photo/magnetic capabilities to address these needs. These CHL micromotors, equipped with phototaxis and photosynthesis abilities, offer promising solutions. A core aspect of this innovation involves incorporating polysaccharides (glycol chitosan (GCS) and fucoidan (F)) into ferric Metal-organic frameworks (MOFs), loaded with urokinase (UK), and subsequently self-assembled onto the multimodal CHL, forming a core-shell microstructure (CHL@GCS/F-UK-MOF). Under light-navigation, CHL@GCS/F-UK-MOF is shown to penetrate thrombi, enhancing thrombolytic biodistribution. Combining CHL@GCS/F-UK-MOF with the magnetic hyperthermia technique achieves stimuli-responsive multiple-release, accelerating thrombolysis and rapidly restoring blocked blood vessels. Moreover, this approach attenuates thrombi-induced ischemic hypoxia disorder and tissue damage. The photosynthetic and magnetotherapeutic properties of CHL@GCS/F-UK-MOF, along with their protective effects, including reduced apoptosis, enhanced behavioral function, induced Heat Shock Protein (HSP), polarized M2 macrophages, and mitigated hypoxia, are confirmed through biochemical, microscopic, and behavioral assessments. This multifunctional biomimetic platform, integrating photo-magnetic techniques, offers a comprehensive approach to cardiovascular management, advancing related technologies.

HSF1/HSP25 system protects mitochondria function from heat stress and assists steroidogenesis in MA-10 Leydig cells

Heat shock response is characterized by the induction of heat shock proteins (HSPs) or molecular chaperones that maintain protein homeostasis. Heat shock transcription factor 1 (HSF1) plays a central role in heat shock response in mammalian cells. To investigate the impact of the heat shock response mechanism on steroidogenesis, we generated MA-10 mouse Leydig tumor cells deficient in HSF1 using CRISPR-Cas9 genome editing. Under heat stress conditions, the levels of StAR protein, but not its mRNA, decreased more in HSF1-knockout cells than in wild-type cells, confirming that HSF1 stabilizes StAR protein. Simultaneously, HSP110, HSP70, and HSP25 were markedly upregulated in a manner dependent on HSF1. Mitochondrial membrane potential (MMP) and ATP synthesis were decreased in HSF1-knockout cells under heat stress conditions, and mitochondrial fragmentation was enhanced. Furthermore, treatment with carbonyl cyanide 3-chlorophenylhydrazone (CCCP), a disruptor of MMP, reduced the levels of StAR protein to a greater extent in HSF1-knockout cells than in wild-type cells, which was associated with decreased MMP and ATP synthesis. Unexpectedly, HSP25 expression was markedly increased in wild-type cells following CCCP treatment. HSP25 knockdown reduces MMP under heat stress conditions and decreases StAR protein levels and progesterone synthesis. HSP25 overexpression in HSF1KO cells restored StAR protein levels. These results show that the HSF1/HSP25 pathway protects mitochondrial function and maintains StAR synthesis.

Copper homeostasis and cuproptosis in gynecological cancers.

Copper (Cu) is an essential trace element involved in a variety of biological processes, such as antioxidant defense, mitochondrial respiration, and bio-compound synthesis. In recent years, a novel theory called cuproptosis has emerged to explain how Cu induces programmed cell death. Cu targets lipoylated enzymes in the tricarboxylic acid cycle and subsequently triggers the oligomerization of lipoylated dihydrolipoamide S-acetyltransferase, leading to the loss of Fe-S clusters and induction of heat shock protein 70. Gynecological malignancies including cervical cancer, ovarian cancer and uterine corpus endometrial carcinoma significantly impact women's quality of life and even pose a threat to their lives. Excessive Cu can promote cancer progression by enhancing tumor growth, proliferation, angiogenesis and metastasis through multiple signaling pathways. However, there are few studies investigating gynecological cancers in relation to cuproptosis. Therefore, this review discusses Cu homeostasis and cuproptosis while exploring the potential use of cuproptosis for prognosis prediction as well as its implications in the progression and treatment of gynecological cancers. Additionally, we explore the application of Cu ionophore therapy in treating gynecological malignancies.

The role of dietary fibre in intestinal heat shock protein regulation

SummaryThe gastrointestinal tract serves as a pivotal physical barrier that prevents the translocation of exogenous substances from the intestinal lumen into the systemic circulation. Dysfunction of intestinal barrier function has been implicated in the pathogenesis of several diseases, such as metabolic disorders. Heat shock proteins (HSPs) play a critical role in maintaining the resilience and viability of epithelial cells when exposed to stressors. Evidence suggests that dietary fibre (DF), a known inducer of HSP production, may be a promising candidate for strengthening the intestinal barrier. Understanding the regulation of intestinal HSPs and the protective effect of DF is critical to defending against environmental threats and preserving human health. To date, six DFs—pectin, chicory, psyllium, guar gum, partially hydrolysed guar gum, and xylooligosaccharide—have been reported to have promotive effects on intestinal HSP induction. DF promotes intestinal HSP induction through gut microbiota‐dependent and independent mechanisms. DF is fermented by gut microbiota to produce short‐chain fatty acids, specifically butyrate and propionate, to promote HSP production. Meanwhile, DF also promotes intestinal HSP induction through direct interaction with intestinal epithelial cells, independent of gut microbiota activity, although the precise mechanism is still unclear. Regulation of intestinal HSP occurs by transcriptional modulation through activation of heat shock transcription factors, primarily heat shock factor 1, or at the post‐transcriptional level by modulation of the translation process. This review highlights recent advances in understanding the role of DF in improving intestinal barrier function, with particular emphasis on the regulatory mechanisms of intestinal HSPs.

HSF1 is required for cellular adaptation to daily temperature fluctuations.

The heat shock response (HSR) is a universal mechanism of cellular adaptation to elevated temperatures and is regulated by heat shock transcription factor 1 (HSF1) or HSF3 in vertebrate endotherms, such as humans, mice, and chickens. We here showed that HSF1 and HSF3 from egg-laying mammals (monotremes), with a low homeothermic capacity, equally possess a potential to maximally induce the HSR, whereas either HSF1 or HSF3 from birds have this potential. Therefore, we focused on cellular adaptation to daily temperature fluctuations and found that HSF1 was required for the proliferation and survival of human cells under daily temperature fluctuations. The ectopic expression of vertebrate HSF1 proteins, but not HSF3 proteins, restored the resistance in HSF1-null cells, regardless of the induction of heat shock proteins. This function was associated with the up-regulation of specific HSF1-target genes. These results indicate the distinct role of HSF1 in adaptation to thermally fluctuating environments and suggest association of homeothermic capacity with functional diversification of vertebrate HSF genes.

Vanadium Toxicity Is Altered by Global Warming Conditions in Sea Urchin Embryos: Metal Bioaccumulation, Cell Stress Response and Apoptosis.

In recent decades, the global vanadium (V) industry has been steadily growing, together with interest in the potential use of V compounds as therapeutics, leading to V release in the marine environment and making it an emerging pollutant. Since climate change can amplify the sensitivity of marine organisms already facing chemical contamination in coastal areas, here, for the first time, we investigated the combined impact of V and global warming conditions on the development of Paracentrotus lividus sea urchin embryos. Embryo-larval bioassays were carried out in embryos exposed for 24 and 48 h to sodium orthovanadate (Na3VO4) under conditions of near-future ocean warming projections (+3 °C, 21 °C) and of extreme warming at present-day marine heatwave conditions (+6 °C, 24 °C), compared to the control temperature (18 °C). We found that the concomitant exposure to V and higher temperature caused an increased percentage of malformations, impaired skeleton growth, the induction of heat shock protein (HSP)-mediated cell stress response and the activation of apoptosis. We also found a time- and temperature-dependent increase in V bioaccumulation, with a concomitant reduction in intracellular calcium ions (Ca2+). This work demonstrates that embryos' sensitivity to V pollution is increased under global warming conditions, highlighting the need for studies on multiple stressors.

Febrile Temperature Acts through HSP70-Toll4 Signaling to Improve Shrimp Resistance to White Spot Syndrome Virus.

In aquatic ectotherms, temperature plays a pivotal role in biological processes and the prevalence of viral diseases; however, the molecular mechanisms underlying these effects are not fully elucidated. In this study, we investigate the impact of elevated temperatures (32°C) on the immune response against white spot syndrome virus (WSSV) in shrimp (Litopenaeus vannamei). Our findings reveal that higher water temperatures, specifically 32°C, significantly inhibit WSSV replication and pathogenicity, thereby enhancing the survival rates of infected shrimp. Through transcriptome analysis and invivo experiments, we identified heat shock protein 70 (HSP70) as a key factor in this thermal regulation of immunity. Shrimp maintained at 32°C, with silenced HSP70 expression, exhibited increased viral loads and reduced survival, underscoring the crucial protective role of HSP70 against WSSV at elevated temperatures. Our results further uncover the HSP70-Toll4-Dorsal-antimicrobial peptide (AMP) pathway as a key mediator of WSSV resistance at elevated temperatures. This pathway involves the interaction of HSP70 with the Toll4 receptor, resulting in the phosphorylation of Dorsal and the consequent modulation of expression of AMPs such as the anti-LPS factor (ALF) and lysozyme (LYZ) families. Taken together, these findings advance our understanding of temperature's role in disease dynamics in aquatic ectotherms, especially the unexpected roles of HSP70 in shrimp in facilitating the innate immune system's response to thermal stress, and suggest new approaches to managing WSSV in shrimp farming, such as environmental temperature control or HSP70 induction.

Oxysterol Induces Expression of 60 kDa Chaperone Protein on Cell Surface of Microglia.

Microglia, essential immune cells in the brain, play crucial roles in neuroinflammation by performing various functions such as neurogenesis, synaptic pruning, and pathogen defense. These cells are activated by inflammatory factors like β-amyloid (Aβ) and oxysterols, leading to morphological and functional changes, including the secretion of inflammatory cytokines and the upregulation of MHC class II molecules. This study focused on identifying specific markers for microglial activation, with a particular emphasis on the roles of oxysterols in this process. We used the HMC3 human microglial cell line to investigate the induction of heat shock protein 60 (HSP60), a chaperonin protein by oxysterols, specifically in the presence of 25-hydroxycholesterol (25OHChol) and 27-hydroxycholesterol (27OHChol). Our findings obtained by the proteomics approach revealed that these oxysterols significantly increased HSP60 expression on microglial cells. This induction was further confirmed using Western blot analysis and immunofluorescence microscopy. Additionally, Aβ1-42 also promoted HSP60 expression, indicating its role as a microglial activator. HSP60 involved in protein folding and immune modulation was identified as a potential marker for microglial activation. This study underscores the importance of HSP60 in the inflammatory response of microglia, suggesting its utility as a target for new therapeutic approaches in neuroinflammatory diseases such as Alzheimer's disease (AD).

The influence of HSP inducers on salinity stress in sterlet sturgeon (Acipenser ruthenus): In vitro study on HSP expression, immune responses, and antioxidant capacity.

Heat shock proteins (HSPs) play a crucial role in antioxidant systems, immune responses, and enzyme activation during stress conditions. Salinity changes can cause stress and energy expenditure in fish, resulting in mortality, especially in fingerlings. The purpose of this study was to examine the relationship between salinity and HSPs in stressed fish by assessing the effects of various HSP inducers (HSPis), including Pro-Tex® (800mM), amygdalin (80mM), and a novel synthetic compound derived from pirano piranazole (80µM), on isolated cells from Sterlet Sturgeon (Acipenser ruthenus) exposed to 13‰ salinity (S13). After liver, kidney, and gill cells were cultured, the HSPi compounds were treated in vitro in the presence and absence of salinity. The expression patterns of HSP27, HSP70, and HSP90 were assessed by Western blotting. Biochemical enzymes (aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase), cortisol levels, and immune parameters (component 3, immunoglobulin M, and lysozyme) were measured before and after treatment with HSPis and HSPi+S13. According to these findings, HSPis positively modulate HSP expression, immune responses, and antioxidant levels. Furthermore, they increased in vitro cell survival by maintaining cortisol levels and biochemical enzyme activities in A. ruthenus under saline conditions (P<0.0001). In conclusion, HSPis can increase A. ruthenus resistance to salinity stress. However, the results also indicated that these compounds can reverse the adverse effects of salinity. The effectiveness of this approach depends on further research into the effects of these ecological factors on the health status of the species, especially in vivo and in combination with other stresses.

Potential of heat shock protein inducers in mitigating benzo[α]pyrene toxicity in stellate sturgeon fingerlings (Acipenser stellatus): Assessing the effects on CYP450 and AChE activity, HSP70 expression, antioxidant levels, cortisol, and immunological responses

AbstractBenzo[α]pyrene (BαP), a polycyclic aromatic hydrocarbon (PAH), is a significant contaminant in the environment, which accumulates and is toxic to invertebrates and fish. The present study aimed to determine the acute toxicity of sublethal concentrations of BαP in the presence of the heat shock protein (HSP) inducer (HSPi) on CYP450 activity, HSP70 gene expression, antioxidant levels, immunological alterations, and AChE activity in stellate sturgeon fingerlings. Two‐hundred and forty fish were exposed to 100 mg L−1 of Nopal endurance (HSPi) for 4 h. In the next step, the fish were exposed to BαP concentrations equivalent to 25%, 50%, and 75% of the 96‐h LC50 values. Sampling was carried out on the first, third, and sixth days of the experiment, and the samples were analyzed using two‐way analysis of variance (ANOVA), cluster analysis (CA), and principal component analysis (PCA). The CYP450 activity significantly increased under BαP treatments. Higher expression of the HSP70 gene was observed in the higher concentration of HSPi + BαP treatments. The lowest AChE activity was observed in BαP treatments. However, the activity of superoxide dismutase, catalase, and total antioxidant activity enzymes and immunological responses (lysozyme, IgM, and C3) increased by using HSPi. It can be concluded that the HSP inducer significantly decreased BαP toxicity and resulted in more resistance to stress situations in sturgeon fingerlings.

Understanding Heat Stress and Tolerance Mechanisms in Wheat (Triticum aestivum L.): A Comprehensive Review

Wheat (Triticum aestivum L.), a vital cereal crop in the Poaceae family, plays a crucial role in global agriculture. It contributes approximately 30% of the world's grain production and constitutes half of the grain traded internationally. Serving as a staple food in over 40 countries, wheat provides essential calories to 85% of the global population and protein to 82%. With the global population expected to reach 9.1 billion by 2050, the Food and Agriculture Organization (FAO) projects that nearly one billion additional tons of cereal will be needed annually to meet increasing demand. Enhancing wheat productivity and production is thus essential. Wheat is cultivated in tropical and subtropical regions, where it faces various abiotic stresses that significantly impact yield, with heat and drought being the most critical challenges. Global climate models predict a potential increase in mean ambient temperature by up to 6°C by the end of the century. Wheat is highly sensitive to heat stress; even a 1°C rise in temperature can reduce global wheat production by 6%. Heat stress affects wheat's physiological, biological, and biochemical processes, including seed germination, grain filling duration, grain number, Rubisco enzyme activity, photosynthetic capacity, assimilate translocation rate, leaf senescence, chlorophyll content, and overall yield. To combat heat stress, wheat has developed diverse tolerance mechanisms. These include the induction of heat shock proteins (HSPs) that assist in proper protein folding and the activation of an antioxidative defense system to detoxify reactive oxygen species (ROS). Traits like Stay Green (SG), chlorophyll fluorescence, and canopy temperature are closely linked to heat tolerance. Understanding and improving these mechanisms are imperative to sustain and enhance wheat production to meet future food demands amidst global climate changes. This review provides a comprehensive analysis of the effects of heat stress on wheat morphology, physiology, and biochemistry. It also discusses the mechanisms of heat tolerance, emphasizing the importance of developing crop varieties capable of withstanding future climatic conditions. Understanding these mechanisms at physiological, biochemical, and morphological levels is crucial for ensuring future food security.

Impact of histone deacetylase inhibition and arimoclomol on heat shock protein expression and disease biomarkers in primary culture models of familial ALS.

Protein misfolding and mislocalization are common themes in neurodegenerative disorders, including motor neuron disease, and amyotrophic lateral sclerosis (ALS). Maintaining proteostasis is a crosscutting therapeutic target, including the upregulation of heat shock proteins (HSP) to increase chaperoning capacity. Motor neurons have a high threshold for upregulating stress-inducible HSPA1A, but constitutively express high levels of HSPA8. This study compared the expression of these HSPs in cultured motor neurons expressing three variants linked to familial ALS: TAR DNA binding protein 43kDa (TDP-43)G348C, fused in sarcoma (FUS)R521G, or superoxide dismutase I (SOD1)G93A. All variants were poor inducers of Hspa1a, and reduced levels of Hspa8 mRNA and protein, indicating multiple compromises in chaperoning capacity. To promote HSP expression, cultures were treated with the putative HSP coinducer, arimoclomol, andclass I histone deacetylase inhibitors, to promote active chromatin for transcription, and with the combination. Treatments had variable, often different effects on the expression of Hspa1a and Hspa8, depending on the ALS variant expressed, mRNA distribution (somata and dendrites), and biomarker of toxicity measured (histone acetylation, maintaining nuclear TDP-43 and the neuronal Brm/Brg-associated factor chromatin remodeling complex component Brg1, mitochondrial transport, FUS aggregation). Overall, histone deacetylase inhibition alone was effective on more measures than arimoclomol. As in the FUS model, arimoclomol failed to induce HSPA1A or preserve Hspa8 mRNA in the TDP-43 model, despite preserving nuclear TDP-43 and Brg1, indicating neuroprotective properties other than HSP induction. The data speak to the complexity of drug mechanisms against multiple biomarkers of ALS pathogenesis, as well as to the importance of HSPA8 for neuronal proteostasis in both somata and dendrites.

A transcriptional enhancer regulates cardiac maturation.

Cardiomyocyte maturation is crucial for generating adult cardiomyocytes and the application of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs). However, regulation at the cis-regulatory element level and its role in heart disease remain unclear. Alpha-actinin 2 (ACTN2) levels increase during CM maturation. In this study, we investigated a clinically relevant, conserved ACTN2 enhancer's effects on CM maturation using hPSC and mouse models. Heterozygous ACTN2 enhancer deletion led to abnormal CM morphology, reduced function and mitochondrial respiration. Transcriptomic analyses in vitro and in vivo showed disrupted CM maturation and upregulated anabolic mammalian target for rapamycin (mTOR) signaling, promoting senescence and hindering maturation. As confirmation, ACTN2 enhancer deletion induced heat shock protein 90A expression, a chaperone mediating mTOR activation. Conversely, targeting the ACTN2 enhancer via enhancer CRISPR activation (enCRISPRa) promoted hPSC-CM maturation. Our studies reveal the transcriptional enhancer's role in cardiac maturation and disease, offering insights into potentially fine-tuning gene expression to modulate cardiomyocyte physiology.

Induction of heat shock protein expression in SP2/0 transgenic cells and its effect on the production of monoclonal antibodies.

The objective of the current investigation was to evaluate the induction of heat shock proteins (HSPs) in SP2/0 transgenic cells and the effect of these proteins on the production of monoclonal antibodies (mAbs). The SP2/0 cell line expressing the PSG-026 antibody, a biosimilar candidate of golimumab, the culture parameters, and the target protein expression were not justified for industrial production and were used for the experiments. Paracetamol and heat shock were used as chemical and physical inducers of HSPs, respectively. The results showed that paracetamol and heat shock increased the expression of HSP70 and HSP27 at the mRNA and protein levels. The expression of HSPs was greater in paracetamol-treated cells than in heat shock-treated cells. Paracetamol treatment at concentrations above 0.5 mM significantly reduced cell viability and mAb expression. However, treatment with 0.25 mM paracetamol results in delayed cell death and increased mAb production. Heat shock treatment at 45°C for 30 minutes after enhanced mAb expression was applied after pre-treatment with paracetamol. In bioreactor cultures, pretreatment of cells with paracetamol improved cell viability and shortened the lag phase, resulting in increased cell density. The production of mAbs in paracetamol-treated cultures was markedly greater than that in the control. Analysis of protein quality and charge variants revealed no significant differences between paracetamol-treated and control cultures, indicating that the induction of HSPs did not affect protein aggregation or charge variants. These findings suggest that inducing and manipulating HSP expression can be a valuable strategy for improving recombinant protein production in biopharmaceutical processes.