Involvement of heparanase in the pathogenesis of acute pancreatitis: Implication of novel therapeutic approaches.

Acute pancreatitis (AP) is a common gastrointestinal disease with high morbidity and mortality rate. Unfortunately, neither the etiology nor the pathophysiology of AP are fully understood and causal treatment options are not available. Recently we demonstrated that heparanase (Hpa) is adversely involved in the pathogenesis of AP and inhibition of this enzyme ameliorates the manifestation of the disease. Moreover, a pioneer study demonstrated that Aspirin has partial inhibitory effect on Hpa. Another compound, which possesses a mild pancreato-protective effect against AP, is Trehalose, a common disaccharide. We hypothesized that combination of Aspirin, Trehalose, PG545 (Pixatimod) and SST0001 (Roneparstat), specific inhibitors of Hpa, may exert pancreato-protective effect better than each drug alone. Thus, the current study examines the pancreato-protective effects of Aspirin, Trehalose, PG545 and SST0001 in experimental model of AP induced by cerulein in wild-type (WT) and Hpa over-expressing (Hpa-Tg) mice. Cerulein-induced AP in WT mice was associated with significant rises in the serum levels of lipase (X4) and amylase (X3) with enhancement of pancreatic edema index, inflammatory response, and autophagy. Responses to cerulein were all more profound in Hpa-Tg mice versus WT mice, evident by X7 and X5 folds increase in lipase and amylase levels, respectively. Treatment with Aspirin or Trehalose alone and even more so in combination with PG545 or SST0001 were highly effective, restoring the serum level of lipase back to the basal level. Importantly, a novel newly synthesized compound termed Aspirlose effectively ameliorated the pathogenesis of AP as a single agent. Collectively, the results strongly indicate that targeting Hpa by using anti-Hpa drug combinations constitute a novel therapy for this common orphan disease.

Inhibition of heme-thiolate monooxygenase CYP1B1 prevents hepatic stellate cell activation and liver fibrosis by accumulating trehalose.

Activation of extracellular matrix-producing hepatic stellate cells (HSCs) is a key event in liver fibrogenesis. We showed that the expression of the heme-thiolate monooxygenase cytochrome P450 1B1 (CYP1B1) was elevated in human and mouse fibrotic livers and activated HSCs. Systemic or HSC-specific ablation and pharmacological inhibition of CYP1B1 attenuated HSC activation and protected male but not female mice from thioacetamide (TAA)-, carbon tetrachloride (CCl4)-, or bile duct ligation (BDL)-induced liver fibrosis. Metabolomic analysis revealed an increase in the disaccharide trehalose in CYP1B1-deficient HSCs resulting from intestinal suppression of the trehalose-metabolizing enzyme trehalase, whose gene we found to be a target of RARα. Trehalose or its hydrolysis-resistant derivative lactotrehalose exhibited potent antifibrotic activity in vitro and in vivo by functioning as an HSC-specific autophagy inhibitor, which may account for the antifibrotic effect of CYP1B1 inhibition. Our study thus reveals an endobiotic function of CYP1B1 in liver fibrosis in males, mediated by liver-intestine cross-talk and trehalose. At the translational level, pharmacological inhibition of CYP1B1 or the use of trehalose/lactotrehalose may represent therapeutic strategies for liver fibrosis.

Photoinactivation of Mycobacterium tuberculosis and Mycobacterium smegmatis by Near-Infrared Radiation Using a Trehalose-Conjugated Heptamethine Cyanine.

The spread of multidrug-resistant mycobacterium strains requires the development of new approaches to combat diseases caused by these pathogens. For that, photodynamic inactivation (PDI) is a promising approach. In this study, a tricarbocyanine (TCC) is used for the first time as a near-infrared (740 nm) activatable PDI photosensitizer to kill mycobacteria with deep light penetration. For better targeting, a novel tricarbocyanine dye functionalized with two trehalose units (TCC2Tre) is developed. The photodynamic effect of the conjugates against mycobacteria, including Mycobacterium tuberculosis, is evaluated. Under irradiation, TCC2Tre causes more effective killing of mycobacteria compared to the photosensitizer without trehalose conjugation, with 99.99% dead vegetative cells of M. tuberculosis and M. smegmatis. In addition, effective photoinactivation of dormant forms of M. smegmatis is observed after incubation with TCC2Tre. Mycobacteria treated with TCC2Tre are more sensitive to 740 nm light than the Gram-positive Micrococcus luteus and the Gram-negative Escherichia coli. For the first time, this study demonstrates the proof of principle of in vitro PDI of mycobacteria including the fast-growing M. smegmatis and the slow-growing M. tuberculosis using near-infrared activatable photosensitizers conjugated with trehalose. These findings are useful for the development of new efficient alternatives to antibiotic therapy.

Effect of Trehalose Disaccharide on Activation of Microglia and Indices of Systemic Inflammation in an Experimental Model of Alzheimer's Disease.

In an experimental model of Alzheimer's disease in mice, oral administration of trehalose disaccharide reduces neuroinflammation assessed by the expression level of microglia activation marker Iba1 and affects the neutrophil degranulation activity. A potential anti-inflammatory effect of 4% trehalose solution associated with a decrease in the activity of leukocyte elastase in plasma was revealed.

Integrative analysis of ex vivo studies and microarray reveals the novel inhibitor effects of trehalose on the pathogenesis of pterygium.

Pterygium is a frequent eye surface condition that is characterized by a high rate of proliferation, fibrovascular development, cellular migration, corneal infiltration, and angiogenesis. We investigated that ex vivo primary pterygium and conjunctival cell cultures were generated to analyze the effect of trehalose on cellular proliferation. After trehalose treatment, we performed microarray analysis to evaluate changes in the mRNA profile. We analyzed gene ontology (GO) and KEGG pathways to identify hub genes that changed expression levels after treatment and were associated with pterygium development. We selected three genes to verify their expression levels using qRT-PCR. The study also evaluated the impact of trehalose treatment on cell migration through a wound-healing assay. Our results suggested that pterygium cell proliferation was inhibited in a dose-dependent manner by trehalose. 2354 DEG were identified in pterygium and conjunctiva cells treated with trehalose compared to untreated groups. Functional enrichment analysis showed that differentially expressed mRNAs are involved in proliferation, vasculature development, and cell migration. We identified ten hub genes including upregulated (RANBP3L, SLC5A3, RERG, ANKRD1, DHCR7, RAB27B, GPRC5B, MSMO1, ASPN, DRAM1) and downregulated (TNC, PTGS2, GREM2, NPTX1, NR4A1, HMOX1, CXCL12, IL6, MYH2, TXNIP). Microarray analysis and functional investigations suggest that trehalose affects the pathogenesis of pterygium by modifying the expression of genes involved in crucial pathways related to cell function.

Trehalose prevents the formation of aggregates of mutant ataxin-3 and reduces soluble ataxin-3 protein levels in an SCA3 cell model.

Spinocerebellar ataxia type 3 (SCA3) is a neurodegenerative disorder caused by mutant ataxin-3 with an abnormally expanded polyQ tract and is the most common dominantly inherited ataxia worldwide. There are no suitable therapeutic options for this disease. Autophagy, a defense mechanism against the toxic effects of aggregation-prone misfolded proteins, has been shown to have beneficial effects on neurodegenerative diseases. Thus, trehalose, which is an autophagy inducer, may have beneficial effects on SCA3. In the present study, we examined the effects of trehalose on an SCA3 cell model. After trehalose treatment, aggregate formation, soluble ataxin-3 protein levels and cell viability were evaluated in HEK293T cells overexpressing ataxin-3-15Q or ataxin-3-77Q. We also explored the mechanism by which trehalose affects autophagy and stress pathways. A filter trap assay showed that trehalose decreased the number of aggregates formed by mutant ataxin-3 containing an expanded polyQ tract. Western blot and Cell Counting Kit-8 (CCK-8) results demonstrated that trehalose also reduced the ataxin-3 protein levels and was safe for ataxin-3-expressing cells, respectively. Western blot and total antioxidant capacity assays suggested that trehalose had great therapeutic potential for treating SCA3, likely through its antioxidant activity. Our data indicate that trehalose plays a neuroprotective role in SCA3 by inhibiting the aggregation and reducing the protein level of ataxin-3, which is also known to protect against oxidative stress. These findings provide a new insight into the possibility of treating SCA3 with trehalose and highlight the importance of inducing autophagy in SCA3.

Multi-layered metabolic effects of trehalose on the liver proteome in apoE-knockout mice model of liver steatosis.

BACKGROUND: Metabolic dysfunction-associated fatty liver disease has been well documented as a key independent risk factor for the development of atherosclerosis. A growing body of evidence suggests that due to its numerous favorable molecular effects, trehalose may exert beneficial effects in counteracting liver steatosis. In our previous study, we described the antiatherosclerotic and antisteatotic properties of trehalose, which we attributed to the induction of autophagy. Considering the pleiotropic activities of trehalose, our present study aimed to extend our preliminary results with the comprehensive examination of proteome-wide changes in the livers of high-fat-fed apoE-/- mice. METHODS: Thus, we applied modern, next-generation proteomic methodology to comprehensively analyze the effects of trehalose on the alterations of liver proteins in apoE-/- mice. RESULTS: Our proteomic analysis showed that the administration of trehalose elicited profound changes in the liver proteome of apoE-/- mice. The collected data allowed the identification and quantitation of 3 681 protein groups of which 129 were significantly regulated in the livers of trehalose-treated apoE-/- mice. CONCLUSIONS: The presented results are the first to highlight the effects of disaccharide on the induction of proteins mainly related to the metabolism and elimination of lipids, especially by peroxisomal ß-oxidation. Our study provides evidence for the pleiotropic activity of trehalose, extending our initial observations of its potential mechanisms responsible for mitigating of liver steatosis, which paves the way for new pharmacological strategies in fatty liver disease.

Impact of protectants and the method of preservation on the stability of potentially probiotic bacteria.

Probiotics offer health advantages when consumed in adequate quantities. As ongoing research identifies promising new strains, ensuring their viability and functionality through simple preservation methods is vital for success within the probiotic industry. This study employed a factorial design to investigate the combined effects of four cryoprotectants [C1: MRS broth + 14 % (w/v) glycerol, C2: Aqueous solution containing 4 % (w/v) trehalose, 6 % (w/v) skimmed milk, and 4 % (w/v) sodium glutamate, C3: Aqueous solution containing 10 % (w/v) skimmed milk and 4 % (w/v) sodium glutamate, C4: Aqueous solution containing 4 % (w/v) sucrose, 6 % (w/v) skimmed milk, and 4 % (w/v) sodium glutamate] and three methods of preservation (P1: -86 °C freezing, P2: -196 °C liquid nitrogen freezing, and P3: storing at 4 °C after lyophilization) on the cell viability of three potentially probiotic strains over 12 months. Pediococcus sp P15 and Weissella cibaria ml6 had the highest viability under treatments C3 and C2, after 12 months of storage, respectively. Meanwhile, Lactococcus lactis ml3 demonstrated the highest viability in both treatments C2 and C4 (P ≤ 0.05). According to the results freezing, either P1 or P2, is the most effective preservation method for P. sp P15 and W. cibaria ml6. Meanwhile, L. lactis ml3 showed the highest colony count under treatment (P1) after 12 months of storage (P ≤ 0.05). Among the tested conditions, P. sp P15 and L. lactis ml3 exhibited the highest viability and bile salt resistance when stored under P1C1. For W. cibaria ml6, the optimal storage condition was P2C2 (frozen in liquid nitrogen with cryoprotectant C2).

Vitrification of medaka whole testis with a trehalose-containing solution and production of medaka individuals derived from the vitrified cells.

The cryopreservation of teleost eggs and embryos remains challenging, and there are no previous reports that demonstrate successful cryopreservation in medaka (Oryzias latipes). We have reported egg and sperm production, followed by the generation of donor-derived offspring by transplanting vitrified whole testes-derived testicular cells into surrogate fish. The vitrification solutions contained ethylene glycol, sucrose, and ficoll. In this study, we replaced sucrose with trehalose in the vitrification solution and medaka whole testes were vitrified with the solution. The post-vitrification survival (72.8 ± 3.5 %) was markedly improved compared with that achieved using the sucrose-containing solution (44.7 ± 4.2 %). Moreover, we demonstrated the production of eggs, sperm, and donor-derived offspring from testicular cells transplanted into surrogate recipients. The phenotype of donor-derived offspring was identical to that of transplanted testicular cells. These findings suggest that trehalose is effective for the vitrification of medaka whole testis and can be considered an effective and reliable method for the long-term preservation of their genetic resources.

Disaccharide-assisted inkjet freezing for improved cell viability.

Non-permeable disaccharides are widely used as cryoprotectant agents due to their low cytotoxicity, but their protective effect is insufficient when the disaccharides are present only extracellularly. On the other hand, cryoprotectant agent (CPA)-free cryopreservation has been recently achieved by instantaneously inkjet-freezing cells as tiny droplets. However, CPA-free cryopreservation requires skilled handling operations due to instability of the vitreous water without the CPA. In this study, the effectiveness of separately adding two types of disaccharides in inkjet freezing of 3T3 cells was evaluated and the following results were obtained. First, trehalose showed the highest effect at 0.57 M, twice the plasma osmolarity, with a maximum cell viability of over 90 % when freezing 70 pL droplets. However, higher concentrations of trehalose decreased cell viability due to damage caused by dehydration. Similarly, sucrose gave cell viability close to 90 % at 0.57 M with 70 pL droplets, and higher concentrations decreased cell viability. Next, the relationship between minimum trehalose concentrations to prevent intracellular and extracellular ice crystal formation and droplet size was analyzed. The results indicated that trehalose of less than 0.57 M was able to inhibit intracellular ice crystal formation even in the largest droplet used in this study, 450 pL, while trehalose of nearly 0.57 M was required to inhibit extracellular ice crystal formation in the smallest droplet, 70 pL. In other words, the suppression of extracellular ice crystals by the addition of CPA was shown to be crucial in improving the viability of inkjet superflash freezing.

Exploring the modulatory effect of trehalose-derived galactooligosaccharides on key gut microbiota groups.

Trehalose (α-d-glucopyranosyl-(1-1)-α-D-glucopyranoside) has found applications in diverse food products as a sweetener, stabilizer, and humectant. Recent attention has focused on trehalose due to its contradictory effects on the virulence of Clostridium difficile. In this study, we investigate the impact of novel trehalose-derived galactooligosaccharides (Treh-GOS) on the human gut microbiota using in vitro fecal fermentation models. Distinct Treh-GOS structures elicit varying taxonomic responses. For instance, ß-Gal-(1-4)-trehalose [DP3(1-4)] leads to an increase of Bifidobacterium, comparable to results observed with commercial GOS. Conversely, ß-Gal-(1-6)-trehalose [DP3(1-6)] prompts an increase in Lactobacillus. Notably, both of these trisaccharides yield the highest concentrations of butyric acid across all samples. On the other hand, Treh-GOS tetrasaccharide mixture (DP4), featuring a novel trehalose galactosylation in both glucose units, fosters the growth of Parabacteroides. Our findings underscore the capacity of novel Treh-GOS to modulate the human gut microbiota. Consequently, these innovative galactooligosaccharides emerge as promising candidates for novel prebiotic applications.

Identification of sulfakinin receptor regulating feeding behavior and hemolymph trehalose homeostasis in the silkworm, Bombyx mori.

Feeding behavior, the most fundamental physiological activity, is controlled by two opposing groups of factors, orexigenic and anorexigenic factors. The sulfakinin family, an insect analogue of the mammalian satiety factor cholecystokinin (CCK), has been shown to suppress food intake in various insects. Nevertheless, the mechanisms through which sulfakinin regulates feeding behavior remain a biological question. This study aimed to elucidate the signaling pathway mediated by the anorexigenic peptide sulfakinin in Bombyx mori. We identified the Bombyx mori neuropeptide G protein-coupled receptor A9 (BNGR-A9) as the receptor for sulfakinin through functional assays. Stimulation with sulfakinin triggered a swift increase in intracellular IP3, Ca2+, and a notable enhancement of ERK1/2 phosphorylation, in a manner sensitive to a Gαq-specific inhibitor. Treatment with synthetic sulfakinin resulted in decreased food consumption and average body weight. Additionally, administering synthetic sulfakinin to silkworms significantly elevated hemolymph trehalose levels, an effect markedly reduced by pre-treatment with BNGR-A9 dsRNA. Consequently, our findings establish the sulfakinin/BNGR-A9 signaling pathway as a critical regulator of feeding behavior and hemolymph trehalose homeostasis in Bombyx mori, highlighting its roles in the negative control of food intake and the positive regulation of energy balance.

Randomized double-blind placebo-controlled trial of the effects of oral trehalose in spinocerebellar ataxia type 3: An interim analysis.

INTRODUCTION: Spinocerebellar ataxia type 3 (SCA3) is a neurodegenerative disease characterized by increasingly worsening ataxia and non-ataxia features, negatively impacting patients' quality of life. This study was designed to test formally evaluate whether oral trehalose was effective in SCA3 patients. METHODS: In this double-blind, randomized controlled trial, SCA3 patients received either 100 g oral trehalose or 30 g maltose to improve ataxia severity over six months. We also measured other clinical (non-ataxia), patient-reported (quality of life, motivations), and safety endpoints. An unscheduled interim analysis was conducted using two-way ANOVAs to analyze the interaction between time (baseline, 3-months, 6-months) and intervention (Trehalose vs. Placebo). RESULTS: Fifteen participants (Trehalose = 7 vs. Placebo = 8) completed the study at the time of interim analysis. There was no interaction effect on the ataxia severity, and available data suggested an estimated sample size of 132 (66 per arm) SCA3 patients required to demonstrate changes in a 6-month trial. There were significant interaction effects for executive function (ƞ2 = 0.28-0.43). Safety data indicated that 100 g oral trehalose was well-tolerated. CONCLUSION: We performed an unplanned interim analysis due to a slow recruitment rate. The new estimated sample size was deemed unfeasible, leading to premature termination of the clinical trial. In this small, current sample of SCA3 patients, 100 g oral trehalose did not differentially impact on ataxia severity compared to placebo. Interestingly, our findings may suggest an improvement in executive function. Future efforts will require a large multi-country, multi-center study to investigate the potential effect of trehalose.

Exploiting sweet relief for preeclampsia by targeting autophagy-lysosomal machinery and proteinopathy.

The etiology of preeclampsia (PE), a severe complication of pregnancy with several clinical manifestations and a high incidence of maternal and fetal morbidity and mortality, remains unclear. This issue is a major hurdle for effective treatment strategies. We recently demonstrated that PE exhibits an Alzheimer-like etiology of impaired autophagy and proteinopathy in the placenta. Targeting of these pathological pathways may be a novel therapeutic strategy for PE. Stimulation of autophagy with the natural disaccharide trehalose and its lacto analog lactotrehalose in hypoxia-exposed primary human trophoblasts restored autophagy, inhibited the accumulation of toxic protein aggregates, and restored the ultrastructural features of autophagosomes and autolysosomes. Importantly, trehalose and lactotrehalose inhibited the onset of PE-like features in a humanized mouse model by normalizing autophagy and inhibiting protein aggregation in the placenta. These disaccharides restored the autophagy-lysosomal biogenesis machinery by increasing nuclear translocation of the master transcriptional regulator TFEB. RNA-seq analysis of the placentas of mice with PE indicated the normalization of the PE-associated transcriptome profile in response to trehalose and lactotrehalose. In summary, our results provide a novel molecular rationale for impaired autophagy and proteinopathy in patients with PE and identify treatment with trehalose and its lacto analog as promising therapeutic options for this severe pregnancy complication.

Cryopreservation of bovine semen using extract of Cinnamomum zeylanicum.

BACKGROUND: Antioxidants minimise oxidative stress and enhance sperm quality in the process of cryopreservation. OBJECTIVE: To assess the impact of Cinnamomum zeylanicum extract as an additive during the post-dilution and post-thaw stages of Murrah buffalo semen cryopreservation. MATERIALS AND METHODS: The semen sample was diluted using Tris-Egg-Yolk-Citric-Acid-Fructose-Glycerol extender and subsequently divided into three groups: Group 1, TEYCAFG without any additives or controls (C); Group 2, TEYCAFG fortified with a 50 ug/mL aqueous extract of cinnamon (T1); and Group 3, TEYCAFG fortified with a 50 ug/mL ethanolic extract of cinnamon (T2). The evaluation included an assessment of progressive motility, live spermatozoa, sperm abnormalities, HOST, CMPT, and enzyme leakage (GOT and GPT) at both the post-dilution and post-thaw stages. RESULTS: The groups that received cinnamon supplementation demonstrated statistically significant improvements (p<0.05) in various parameters, including an increase in the progressive motility, live spermatozoa, and HOS-positive spermatozoa, as well as greater distance traveled by vanguard spermatozoa compared to the control group. Furthermore, the cinnamon-added groups exhibited a significant decrease (p<0.05) in the percentage of sperm abnormalities and lower enzyme leakage (GOT and GPT) in post-thawed semen. CONCLUSION: Aqueous extract of C. zeylanicum at a concentration of 50 µg/mL provides superior protection of sperm structures and functions as compared to both the ethanolic extract of C. zeylanicum at the same concentration and the control group. Doi.org/10.54680/fr24310110712.

Targeting autophagy impairment improves the phenotype of a novel CLN8 zebrafish model.

CLN8 is an endoplasmic reticulum cargo receptor and a regulator of lysosome biogenesis whose loss of function leads to neuronal ceroid lipofuscinosis. CLN8 has been linked to autophagy and lipid metabolism, but much remains to be learned, and there are no therapies acting on the molecular signatures in this disorder. The present study aims to characterize the molecular pathways involved in CLN8 disease and, by pinpointing altered ones, to identify potential therapies. To bridge the gap between cell and mammalian models, we generated a new zebrafish model of CLN8 deficiency, which recapitulates the pathological features of the disease. We observed, for the first time, that CLN8 dysfunction impairs autophagy. Using autophagy modulators, we showed that trehalose and SG2 are able to attenuate the pathological phenotype in mutant larvae, confirming autophagy impairment as a secondary event in disease progression. Overall, our successful modeling of CLN8 defects in zebrafish highlights this novel in vivo model's strong potential as an instrument for exploring the role of CLN8 dysfunction in cellular pathways, with a view to identifying small molecules to treat this rare disease.

Protective effect of trehalose sugar on amyloid-membrane interactions using BLM electrophysiology.

Alzheimer's disease (AD) is a neurodegenerative disease characterized by dementia and memory loss in the elderly population. The amyloid-ß peptide (Aß) is one of the main pathogenic factors in AD and is known to cause damage to neuronal cellular membranes. There is no cure currently available for AD, and new approaches, including preventive strategies, are highly desirable. In this work, we explore the possibility of protecting neuronal membranes from amyloid-induced damage with naturally existing sugar trehalose. Trehalose has been shown to protect plant cellular membranes in extreme conditions and modify Aß misfolding. We hypothesize that trehalose can protect the neuronal membrane from amyloid toxicity. In this work, we studied the protective effect of trehalose against Aß1-42-induced damage in model lipid membranes (DPPC/POPC/cholesterol) using atomic force microscopy and black lipid membrane electrophysiology. Our results demonstrate that Aß1-42 damaged membranes and led to ionic current leakage across these membranes due to the formation of various defects and pores. The presence of trehalose reduced the ion current across membranes caused by Aß1-42 peptide damage, thus efficiently protecting the membranes. These findings suggest that the trehalose sugar can potentially be useful in protecting neuronal membranes against amyloid toxicity in AD.

Exploration of novel trehalases from cold-adapted Variovorax sp. PAMC28711: Functional characterization.

The cold-adapted bacterium Variovorax sp. PAMC28711 possesses two distinct glycoside hydrolase (GH) families of trehalase, GH15 and GH37. While numerous studies have explored bacterial trehalase, the presence of two different trehalase genes within a single strain has not been reported until now. Interestingly, despite both GH37 and GH15 trehalases serving the same purpose of degrading trehalose, but do not share the sequence similarity. The substrate specificity assay confirmed that Vtre37 and Vtre15 displayed hydrolytic activity on α, α-trehalose. The key catalytic sites were identified as D280 and E469 in Vtre37 and E389 and E554 in Vtre15 through site-directed mutation and confirmed these two enzymes belong to trehalase. In addition, Vtre37 exhibited a relatively high level of enzyme activity of 1306.33 (±53.091) µmolmg-1, whereas Vtre15 showed enzyme activity of 408.39 (±12.503) µmolmg-1. Moreover, Vtre37 performed admirably showing resistance to ethanol (10 %), with high stable at acidic pH range. Furthermore, both prediction and experimental results indicate that validoxylamine A showed a potent inhibitory activity against Vtre37 trehalase with a Ki value of 16.85 nM. Therefore, we postulate that Vtre37 could be utilized as an ethanol enhancer and designed for screening inhibitors related to the trehalose degradation pathway. Additionally, we believe that characterizing these bacterial trehalase contributes to a better understanding of trehalose metabolism and its biological importance in bacteria.

Transcriptome analysis reveals that trehalose alleviates chilling injury of peach fruit by regulating ROS signaling pathway and enhancing antioxidant capacity.

Peach fruit is prone to chilling injury (CI) during low-temperature storage, resulting in quality deterioration and economic losses. Our previous studies have found that exogenous trehalose treatment can alleviate the CI symptoms of peach by increasing sucrose accumulation. The purpose of this study was to explore the potential molecular mechanism of trehalose treatment in alleviating CI in postharvest peach fruit. Transcriptome analysis showed that trehalose induced gene expression in pathways of plant MAPK signaling, calcium signaling, and reactive oxygen species (ROS) signaling. Furthermore, molecular docking analysis indicated that PpCDPK24 may activate the ROS signaling pathway by phosphorylating PpRBOHE. Besides, PpWRKY40 mediates the activation of PpMAPKKK2-induced ROS signaling pathway by interacting with the PpRBOHE promoter. Accordingly, trehalose treatment significantly enhanced the activities of antioxidant-related enzymes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and gluathione reductase (GR), as well as the transcription levels AsA-GSH cycle related gene, which led to the reduction of H2O2 and malondialdehyde (MDA) content in peach during cold storage. In summary, our results suggest that the potential molecular mechanism of trehalose treatment is to enhance antioxidant capacity by activating CDPK-mediated Ca2 + -ROS signaling pathway and WRKY-mediated MAPK-WRKY-ROS signaling pathway, thereby reducing the CI in peach fruit.