Episymbiotic bacterium induces intracellular lipid droplet production in its host bacteria.

Saccharibacteria (formerly TM7) Nanosynbacter lyticus type strain TM7x exhibits a remarkably compact genome and an extraordinarily small cell size. This obligate epibiotic parasite forms a symbiotic relationship with its bacterial host, Schaalia odontolytica , strain XH001 (formerly Actinomyces odontolyticus strain XH001). Due to its limited genome size, TM7x possesses restrained metabolic capacities, predominantly living on the surface of its bacterial host to sustain this symbiotic lifestyle. To comprehend this intriguing, yet understudied interspecies interaction, a thorough understanding of the physical interaction between TM7x and XH001 is imperative. In this study, we employed super-resolution fluorescence imaging to investigate the physical association between TM7x and XH001. We found that the binding with TM7x led to a substantial alteration in the membrane fluidity of the host bacterium XH001. Unexpectedly, we revealed the formation of intracellular lipid droplets in XH001 when forming episymbiosis with TM7x, a feature not commonly observed in oral bacteria cells. The TM7x-induced LD accumulation in XH001 was further confirmed by label-free non-invasive Raman spectroscopy, which also unveiled additional phenotypical features when XH001 cells are physically associated with TM7x. Further exploration through culturing host bacterium XH001 alone under various stress conditions showed that LD accumulation was a general response to stress. Intriguingly, a survival assay demonstrated that the presence of LDs likely plays a protective role in XH001, enhancing its overall survival under adverse conditions. In conclusion, our study sheds new light on the intricate interaction between Saccharibacteria and its host bacterium, highlighting the potential benefit conferred by TM7x to its host, and further emphasizing the context-dependent nature of symbiotic relationships.

Near-infrared photodynamic and photothermal co-therapy based on organic small molecular dyes.

Near-infrared (NIR) organic small molecule dyes (OSMDs) are effective photothermal agents for photothermal therapy (PTT) due to their advantages of low cost and toxicity, good biodegradation, and strong NIR absorption over a wide wavelength range. Nevertheless, OSMDs have limited applicability in PTT due to their low photothermal conversion efficiency and inadequate destruction of tumor regions that are nonirradiated by NIR light. However, they can also act as photosensitizers (PSs) to produce reactive oxygen species (ROS), which can be further eradicated by using ROS-related therapies to address the above limitations of PTT. In this review, the synergistic mechanism, composition, and properties of photodynamic therapy (PDT)-PTT nanoplatforms were comprehensively discussed. In addition, some specific strategies for further improving the combined PTT and PDT based on OSMDs for cancer to completely eradicate cancer cells were outlined. These strategies include performing image-guided co-therapy, enhancing tumor infiltration, increasing H2O2 or O2 in the tumor microenvironment, and loading anticancer drugs onto nanoplatforms to enable combined therapy with phototherapy and chemotherapy. Meanwhile, the intriguing prospects and challenges of this treatment modality were also summarized with a focus on the future trends of its clinical application.

A Comprehensive Comparative Analysis of Deep Learning Based Feature Representations for Molecular Taste Prediction.

Taste determination in small molecules is critical in food chemistry but traditional experimental methods can be time-consuming. Consequently, computational techniques have emerged as valuable tools for this task. In this study, we explore taste prediction using various molecular feature representations and assess the performance of different machine learning algorithms on a dataset comprising 2601 molecules. The results reveal that GNN-based models outperform other approaches in taste prediction. Moreover, consensus models that combine diverse molecular representations demonstrate improved performance. Among these, the molecular fingerprints + GNN consensus model emerges as the top performer, highlighting the complementary strengths of GNNs and molecular fingerprints. These findings have significant implications for food chemistry research and related fields. By leveraging these computational approaches, taste prediction can be expedited, leading to advancements in understanding the relationship between molecular structure and taste perception in various food components and related compounds.

Association of body mass index from childhood to mid-adulthood with health-related quality of life in mid-adulthood.

PURPOSE: Most studies regarding the association of obesity with health-related quality of life (HRQoL) have assessed obesity at only one or two time points. We aimed to examine the associations of life course body mass index (BMI) from childhood with health-related quality of life (HRQoL) in mid-adulthood. METHODS: Data were from a cohort study of Australian children (n = 2254, mean baseline age 12.0 (2.0) years in 1985, 46.8% male). Weight and height were measured at baseline and measured or self-reported on average 20, 25, and 30 years later. Age and sex-standardised BMI-z score was calculated at each time point. Physical and mental HRQoL and health state utilities (HSUs) were measured by SF-12 and SF-6D at the last adult follow-up. Linear regression was used to examine the associations adjusting for age, sex, and childhood health status. RESULTS: Higher BMI-z score in childhood (ßadjusted - 1.39, 95% CI - 1.73 to - 1.05) and increasing BMI-z score from childhood to young adulthood (ßadjusted - 1.82, 95% CI - 2.17 to - 1.46) and from young to mid-adulthood (ßadjusted - 1.77, 95% CI - 2.28 to - 1.26) were associated with lower physical HRQoL in mid-adulthood. Similar results were found for mid-adulthood HSUs (ßadjusted ranged - 0.006 to - 0.014, all P < 0.05). Only increasing BMI-z score from young to mid-adulthood significantly related to poorer mental HRQoL (ßadjusted - 0.74, 95% CI - 1.29 to - 0.19) in mid-adulthood. CONCLUSION: High BMI from childhood to mid-adulthood had only modest associations with HRQoL and HSUs, with effects on physical HRQoL most apparent.

Development and validation of the atopic dermatitis and infant skincare knowledge, attitude, and practice (ADISKAP 1.0) scale.

Importance: Preserving skin health is crucial for atopic dermatitis control as well as for the thriving of children. However, a well-developed and validated tool that measures the knowledge, attitude, and practice of skin care is lacking. Objective: To develop and validate the atopic dermatitis and infant skincare knowledge, attitude, and practice (ADISKAP 1.0) scale that measures parental health literacy on atopic dermatitis and skin care. Methods: We conducted a review of the literature, a focus group (two dermatologists and 12 parents), and a panel discussion in order to generate the ADISKAP prototype. Two samples of parents with knowingly superior (dermatologists, n = 59) and inferior (general population, n = 395) knowledge traits participated in the validation of ADISKAP. Cronbach's alpha was reported as a measure of internal consistency, and the intraclass correlation coefficient (ICC) was calculated to assess the test-retest validity. The known-groups technique was used to evaluate construct validity. Results: The ADISKAP scale contained 17 items after content and face validity validation. After removing items that displayed poor test-retest reliability (n = 4) and construct validity (n = 3), 12 items were retained in the ADISKAP 1.0. Interpretation: ADISKAP 1.0 is a reliable and valid tool for assessing parental knowledge, attitude, and practice on infantile atopic dermatitis and skin care.

Endoscopic Ruler for varix size measurement: A multicenter pilot study.

BACKGROUND: We invented Endoscopic Ruler, a new endoscopic device to measure the size of varices in patients with cirrhosis and portal hypertension. AIM: To assess the feasibility and safety of Endoscopic Ruler, and evaluate the agreement on identifying large oesophageal varices (OV) between Endoscopic Ruler and the endoscopists, as well as the interobserver agreement on diagnosing large OV using Endoscopic Ruler. METHODS: We prospectively and consecutively enrolled patients with cirrhosis from 11 hospitals, all of whom got esophagogastroduodenoscopy (EGD) with Endoscopic Ruler. The primary study outcome was a successful measurement of the size of varices using Endoscopic Ruler. The secondary outcomes included adverse events, operation time, the agreement of identifying large OV between the objective measurement of Endoscopic Ruler and the empirical reading of endoscopists, together with the interobserver agreement on diagnosing large OV by Endoscopic Ruler. RESULTS: From November 2020 to April 2022, a total of 120 eligible patients with cirrhosis were recruited and all of them underwent EGD examinations with Endoscopic Ruler successfully without any adverse event. The median operation time of Endoscopic Ruler was 3.00 min [interquartile range (IQR): 3.00 min]. The kappa value between Endoscopic Ruler and the endoscopists while detecting large OV was 0.52, demonstrating a moderate agreement. The kappa value for diagnosing large OV using Endoscopic Ruler among the six independent observers was 0.77, demonstrating a substantial agreement. CONCLUSION: The data demonstrates that Endoscopic Ruler is feasible and safe for measuring the size of varices in patients with cirrhosis and portal hypertension. Endoscopic Ruler is potential to promote the clinical practice of the two-grade classification system of OV.

Unveiling novel insights in prostate cancer through single-cell RNA sequencing.

Single-cell RNA sequencing (scRNA-seq) is a cutting-edge technology that provides insights at the individual cell level. In contrast to traditional bulk RNA-seq, which captures gene expression at an average level and may overlook important details, scRNA-seq examines each individual cell as a fundamental unit and is particularly well-suited for identifying rare cell populations. Analogous to a microscope that distinguishes various cell types within a tissue sample, scRNA-seq unravels the heterogeneity and diversity within a single cell species, offering great potential as a leading sequencing method in the future. In the context of prostate cancer (PCa), a disease characterized by significant heterogeneity and multiple stages of progression, scRNA-seq emerges as a powerful tool for uncovering its intricate secrets.

Hyperglycemia-regulated tRNA-derived fragment tRF-3001a propels neurovascular dysfunction in diabetic mice.

Neurovascular dysfunction is a preclinical manifestation of diabetic complications, including diabetic retinopathy (DR). Herein, we report that a transfer RNA-derived RNA fragment, tRF-3001a, is significantly upregulated under diabetic conditions. tRF-3001a downregulation inhibits Müller cell activation, suppresses endothelial angiogenic effects, and protects against high-glucose-induced retinal ganglion cell injury in vitro. Furthermore, tRF-3001a downregulation alleviates retinal vascular dysfunction, inhibits retinal reactive gliosis, facilitates retinal ganglion cell survival, and preserves visual function and visually guided behaviors in STZ-induced diabetic mice and db/db diabetic mice. Mechanistically, tRF-3001a regulates neurovascular dysfunction in a microRNA-like mechanism by targeting GSK3B. Clinically, tRF-3001a is upregulated in aqueous humor (AH) samples of DR patients. tRF-3001a downregulation inhibits DR-induced human retinal vascular endothelial cell and Müller cell dysfunction in vitro and DR-induced retinal neurovascular dysfunction in C57BL/6J mice. Thus, targeting tRF-3001a-mediated signaling is a promising strategy for the concurrent treatment of vasculopathy and neuropathy in diabetes mellitus.

Effect of Mind Map Health Education Mode on Prevention of Pressure Ulcers.

Objective: This work aimed to develop a pressure ulcer prevention nursing and health education strategy by using mind map techniques, apply the strategy to critically ill inpatients, and evaluate its effect on preventing pressure ulcers in patients. Methods: A study population of 82 critically ill hospitalized patients received random assignments to the control group (routine nursing intervention, n = 41) and the observation group (mental map health education based on the control group, n = 20). Patients in each group were then compared for the incidence and knowledge of pressure ulcers before and after nursing intervention and health education. Results: The awareness rates of pressure ulcer knowledge in the control and observation groups were 78.85% and 94.21%, respectively. The awareness rates of prevention knowledge after intervention were 79.8% and 94.38%, respectively (P < .05). The proportion of patients with a high risk of pressure ulcers in the observation group was lower than that in the control group (P < .05). The proportion of patients with a mild risk of pressure ulcers in the observation group was higher than in the control group (P < .05). Stage I pressure ulcers in the control and observation groups were 12.3% and 3.65%, respectively (P < .05). The incidence of stage II and above pressure ulcers in the control group and the observation group were 25.8% and 20.1%, respectively (P < .05). Conclusions: The mind map health education model helped improve patients' cognition level of pressure ulcers and enhanced their awareness of active cooperation, significantly preventing pressure ulcers.

Preoperative vascular heterogeneity based on dynamic susceptibility contrast MRI in predicting spatial pattern of locally recurrent high-grade gliomas.

OBJECTIVES: To investigate if spatial recurrence pattern is associated with patient prognosis, and whether MRI vascular habitats can predict spatial pattern. METHODS: In this retrospective study, 69 patients with locally recurrent high-grade gliomas (HGGs) were included. The cohort was divided into intra-resection cavity recurrence (ICR) and extra-resection cavity recurrence (ECR) patterns, according to the distance between the location of the recurrent tumor and the resection cavity or surgical region. Four vascular habitats, high angiogenic tumor, low angiogenic tumor, infiltrated peripheral edema, and vasogenic peripheral edema, were segmented and vascular heterogeneity parameters were analyzed. The survival and diagnostic performance under different spatial recurrence patterns were analyzed by Kaplan-Meier and ROC. A nomogram model was constructed by regression analysis and validated by bootstrapping technique. RESULTS: Progression-free survival (PFS) and overall survival (OS) were longer for ICR (n = 32) than those for ECR (n = 37) (median PFS: 8 vs. 5 months, median OS: 17 vs. 13 months, p < 0.05). MRI vascular habitat analyses showed ECR had higher median relative cerebral blood volume (rCBVmedian) at each habitat than ICR (all p < 0.01). The rCBVmedian at IPE had good diagnostic performance (AUC: 0.727, 95%CI: 0.607, 0.828). The AUC of the nomogram based on MRI vascular habitats and clinical factors was 0.834 (95%CI: 0.726, 0.913) and was confirmed as 0.833 (95%CI: 0.830, 0.836) by bootstrapping validation. CONCLUSIONS: The spatial pattern of locally recurrent HGGs is associated with prognosis. MRI vascular heterogeneity parameter could be used as a non-invasive imaging marker to predict spatial recurrence pattern. CLINICAL RELEVANCE STATEMENT: Vascular heterogeneity parameters based on MRI vascular habitat analyses can non-invasively predict the spatial patterns of locally recurrent high-grade gliomas, providing a new diagnostic basis for clinicians to develop the extent of surgical resection and postoperative radiotherapy planning. KEY POINTS: • Intra-resection cavity pattern was associated with longer progression-free survival and overall survival in locally recurrent high-grade gliomas. • Higher vascular heterogeneities in extra-resection cavity recurrence than in intra-resection cavity recurrence and the vascular heterogeneity parameters had good diagnostic performance in discriminating spatial recurrence pattern. • A nomogram model based on MRI vascular habitats and clinical factors had good performance in predicting spatial recurrence pattern.

A case series on the efficacy and safety of a PD-1 inhibitor combined with antiangiogenic agents in the treatment of recurrent MSI-H endometrial cancer.

Background: Endometrial cancer (EC) is one of the most common gynecological malignancies in developed countries worldwide. The treatment of recurrent endometrial cancer is a very difficult problem in clinical work. Studies on patients with recurrent EC microsatellite instability-high (MSI-H) are very rare. The objective of this study is to initially evaluate the therapeutic effect of a PD-1 inhibitor combined with antiangiogenic agents in the treatment of recurrent MSI-H endometrial cancer. Methods: Eight patients with recurrent MSI-H endometrial cancer were recruited from Tianjin Medical University Cancer Institute and Hospital from July 2019 to July 2021, and their median age was 55.3 (range, 46-62) years. All patients experienced recurrence after surgical treatment, and the median recurrence and metastasis time was 6.6 (range, 4-10) months. The pathological types were all endometrioid carcinomas. PD-1 inhibitors were selected from camrelizumab or pembrolizumab, and antiangiogenic targeted agents were selected from apatinib or anlotinib. Results: The median follow-up time was 11.0 (range, 5-19) months. In the case series, all 8 cases could be evaluated for curative effect with complete response in 4 cases and partial response in 4 cases. The overall objective response rate was 100%. Conclusions: PD-1 inhibitors combined with antiangiogenic agents may have good therapeutic effects on patients with recurrent MSI-H endometrial cancer and may become an important method for the treatment of recurrent endometrial cancer in the future.

Agomelatine enhances the therapeutic effect of venlafaxine on depression and improves the levels of S100B and GFAP.

OBJECTIVE: To determine the efficacy of venlafaxine combined with agomelatine in elderly patients with depression and observe the changes in S-100 calcium binding protein B (S-100B) and glial fibrillary acidic protein (GFAP) before and after treatment. METHODS: The data of 142 elderly patients with depression treated in Affiliated Hospital of Gansu Medical College between January 2020 and January 2022 were retrospectively studied. Among the patients, 62 treated with venlafaxine were assigned to a control group, and 80 treated with agomelatine combined with venlafaxine were assigned to an observation group. In addition, 50 patients with suspected meningitis who were treated in Affiliated Hospital of Gansu Medical College over the same time span were enrolled into a normal group. The two groups of patients were compared in terms of clinical efficacy after treatment and the changes in S100B and GFAP before and after treatment. The diagnostic value of S100B and GFAP in patients with depression was explored. Additionally, the changes in Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) score before and after treatment were compared between the two groups, and the adverse drug reaction rate was also compared. RESULTS: The patient group showed higher cerebrospinal fluid (CSF) levels of S100B and GFAP than the control group (P < 0.001). The areas under the curve (AUC) of CSF S100B and GFAP for diagnosing depression were 0.833 and 0.925, respectively, and the AUC of the combination of the two was 0.967, which was larger than that of CSF S100B or GFAP alone (P < 0.001). Additionally, the control group showed lower clinical efficacy than the observation group (P < 0.001). After treatment, the observation group exhibited lower CSF levels of S100B and GFAP than the control group (P < 0.001), and demonstrated higher RBANS score than the control group (P < 0.001). The difference in adverse drug reaction rate was not significant between the control group and the observation group (P > 0.05). CONCLUSION: S100B and GFAP can be used as diagnostic indicators of depression. Agomelatine plus venlafaxine are superior to venlafaxine alone in the treatment of depression. The combination can contribute to better S100B and GFAP levels, and take a more obvious role in alleviating disease symptoms, thereby improving the cognitive function and overall well-being of patients.

A Janus supramolecular hydrogel prepared by one-pot method for wound dressing.

Despite the adhesive hydrogels have gained progress and popularity, it is still an enormous challenge to develop a smart adhesion hydrogel for clinical medicine, which is an asymmetric adhesion hydrogel with on-demand detachment. Motivated by the thermal phase transition mechanism of gelatin, we have synthesized a Janus supramolecular hydrogel dressing with skin temperature-triggered adhesion by a simple one-pot process. This hydrogel has asymmetric and controllable adhesion, which not only can become the external objects barrier but also can achieve repeated adhesion and on-demand detachment triggered by temperature in tens of seconds. This hydrogel presents great mechanical performance (compressive strain of 65 %, 1.38 MPa) owing to the presence of supramolecular interactions in the hydrogel. Additionally, this hydrogel exhibits excellent antibacterial activity and biocompatibility. The synergistic effect of modified gelatin and ionic liquid greatly facilitates wound healing of full-thickness skin with high wound healing efficiency (98.45 %). Therefore, thanks to all these advantages, the Janus supramolecular hydrogel can be applied for wound management and treatment, which has huge potential in healing skin wounds.

Metabolic Syndrome and Inflammation from Young to Mid-Adulthood and Subclinical Kidney Damage in Middle-Aged Australians.

Background: Relationships between metabolic syndrome (MetS), inflammation, and chronic kidney disease (CKD) have been reported, but long-term follow-up studies are limited. This study aimed to investigate whether MetS and C-reactive protein (CRP) from young adulthood associated with the risk of subclinical kidney damage (SKD), a surrogate measure for CKD, in mid-adulthood. Materials and Methods: One thousand fifteen participants from the Childhood Determinants of Adult Health study aged 26-36 years at baseline (2004-2006) were followed up at age 36-49 (2014-2019). Log-binomial regression was used to determine whether MetS and high CRP in young adulthood and from young to mid-adulthood predicted the risk of SKD (an estimated glomerular filtration rate [eGFR] of 30-60 mL/min/1.73 m2 or an eGFR >60 mL/min/1.73 m2 with a urine albumin-creatinine ratio ≥2.5 mg/mmol [males] or ≥3.5 mg/mmol [females]) in midlife. Results: Having MetS in young adulthood was associated with an increased risk of SKD in midlife (adjusted relative risk [aRR] = 2.67, 95% confidence interval [CI]: 1.24-5.76). Participants with MetS and high CRP as young adults had a greater risk of having SKD in midlife (aRR = 4.27, 95% CI: 1.61-11.30) compared with those without MetS and high CRP. Furthermore, for participants with persistent MetS, the aRR of SKD in midlife was 4.08 (95% CI: 1.84-9.05) compared with those without MetS from young to mid-adulthood. No significant associations were found between CRP in young adulthood, or change in CRP from young to mid-adulthood, and SKD in midlife. Conclusions: MetS in young adulthood, with and without high CRP, and persistent MetS were associated with an increased risk of SKD in middle midlife.

The mercury flow through a terrestrial songbird food chain in subtropical pine forest: Elucidated by Bayesian isotope mixing model and stable mercury isotopes.

In order to comprehend the transfer of inorganic mercury (IHg) and methylmercury (MeHg) within food chains in terrestrial pine forests, we collected samples of Great Tit nestlings, common invertebrates, plants, and soil in a subtropical pine forest and used Bayesian isotope mixing model analysis, Hg daily intake, and stable Hg isotopes to elucidate the flow of MeHg and IHg in these food chains. Results indicate that caterpillars and cockroaches are the predominant prey items for nestlings, accounting for a combined contribution of 81.5%. Furthermore, caterpillars, cockroaches, and spiders were found to contribute the most (∼80%) of both IHg and MeHg that dietary accumulated in nestlings. The provisoned invertebrates tend to supply more IHg and diluting the proportion of MeHg as total Hg (MeHg%). Notably, nestling feathers displayed the highest Δ199Hg values but a relatively lower MeHg%, suggesting an imbalanced incorporation of Hg from maternal transfer and dietary accumulation during the nestling stage. This study highlights the efficacy of nestlings as indicators for identifying Hg sources and transfers in avian species and food chains. However, caution must be exercised when using Hg isotope compositions in growing feathers, and the contribution of maternally transferred Hg should not be ignored.

Interleukin-33 improves the neurogenesis of neural stem cells in perinatal brain after hypoxia-ischemia.

Perinatal hypoxia-ischemia (HI) insult is an important cause of neonatal encephalopathy, and the effective therapeutic approaches are currently limited. Interleukin (IL)-33 acts as a member of the IL-1 superfamily and has been shown to be neuroprotective following experimental neonatal HI and adult stroke. Here, we explore the effect of IL-33 and its specific receptor ST2 axis on endogenous neurogenesis in neonatal brain after HI. ST2 was found on the surface of NSCs, and the expression of ST2 was further enhanced after HI challenge. Delivery of IL-33 obviously repopulated the size of NSC pool, whereas ST2 deficiency worsened the neurogenesis of NSCs in neonatal brain post HI insult. Further in vivo and in vitro studies showed IL-33 regulates the survival, proliferation and differentiation of NSCs through ST2 signaling pathways. Intriguingly, IL-33 facilitated translocation of Nrf2 from the cytoplasm to the nucleus, which is involved in neural differentiation of NSCs. These data demonstrate a critical role of IL-33/ST2 axis in regulation of endogenous neurogenesis of NSCs via activation of the Nrf2 signaling, which provide a new insight into the effect of IL-33 in neonatal brain following HI injury.

A novel multi-scale pressure sensing hydrogel for monitoring the physiological signals of long-term bedridden patients.

For long-term bedridden patients who need to wear diapers, the timely replacement of diapers is very important to ensure their quality of life. Therefore, it is urgent to develop a pressure sensor that can monitor the physiological conditions of patients in real time. Inspired by the multi-scale network structure of the multi-fiber protein in the muscle, a multi-scale hydrogel as a pressure sensor was prepared by introducing micron-scale hydrogel microspheres as physical crosslinking agents. Compared with the traditional polyacrylamide hydrogel (0.17 MPa of compressive strength), the multi-scale hydrogel showed a higher compressive strength of up to 1.37 MPa. Meanwhile, the hydrogel exhibited better pressure sensitivity (0.59 kPa-1) than the existing hydrogels (0.27-0.40 kPa-1). The sensor prepared by this hydrogel could monitor the patient's physiological condition (urine outflow and urinary filling) in real time through the conductivity response to ion concentration and pressure, and then transmit the signal to the caregivers in time to avoid skin damage. This multi-scale hydrogel provided a great convenience for the physiological monitoring of long-term bedridden patients by acting as a pressure sensor.

Contribution of HIF-1α to Heat Shock Response by Transcriptional Regulation of HSF1/HSP70 Signaling Pathway in Pacific Oyster, Crassostrea gigas.

Ocean temperature rising drastically threatens the adaptation and survival of marine organisms, causing serious ecological impacts and economic losses. It is crucial to understand the adaptive mechanisms of marine organisms in response to high temperature. In this study, a novel regulatory mechanism that is mediated by hypoxia-inducible factor-1α (HIF-1α) was revealed in Pacific oyster (Crassostrea gigas) in response to heat stress. We identified a total of six HIF-1α genes in the C. gigas genome, of which HIF-1α and HIF-1α-like5 were highly induced under heat stress. We found that the HIF-1α and HIF-1α-like5 genes played critical roles in the heat shock response (HSR) through upregulating the expression of heat shock protein (HSP). Knocking down of HIF-1α via RNA interference (RNAi) inhibited the expression of heat shock factor 1 (HSF1) and HSP70 genes in C. gigas under heat stress. Both HIF-1α and HIF-1α-like5 promoted the transcriptional activity of HSF1 by binding to hypoxia response elements (HREs) within the promoter region. Furthermore, the survival of C. gigas under heat stress was significantly decreased after knocking down of HIF-1α. This work for the first time revealed the involvement of HIF-1α/HSF1/HSP70 pathway in response to heat stress in the oyster and provided an insight into adaptive mechanism of bivalves in the face of ocean warming.