The impact of nanomaterials on autophagy across health and disease conditions

Autophagy, a catabolic process integral to cellular homeostasis, is constitutively active under physiological and stress conditions. The role of autophagy as a cellular defense response becomes particularly evident upon exposure to nanomaterials (NMs), especially environmental nanoparticles (NPs) and nanoplastics (nPs). This has positioned autophagy modulation at the forefront of nanotechnology-based therapeutic interventions. While NMs can exploit autophagy to enhance therapeutic outcomes, they can also trigger it as a pro-survival response against NP-induced toxicity. Conversely, a heightened autophagy response may also lead to regulated cell death (RCD), in particular autophagic cell death, upon NP exposure. Thus, the relationship between NMs and autophagy exhibits a dual nature with therapeutic and environmental interventions. Recognizing and decoding these intricate patterns are essential for pioneering next-generation autophagy-regulating NMs. This review delves into the present-day therapeutic potential of autophagy-modulating NMs, shedding light on their status in clinical trials, intervention of autophagy in the therapeutic applications of NMs, discusses the potency of autophagy for application as early indicator of NM toxicity.

Evolutionary analysis and quality assessment of ζ-carbonic anhydrase sequences from environmental microbiome

Carbonic anhydrase (CA) is one of the most vital enzymes in living cells. This study has been performed due to the significance of this metalloenzyme for life and the novelty of some CA families like ζ-CA to evaluate evolutionary processes and quality check their sequences. In this study, bioinformatics methods revealed the presence of ζ-CA in some eukaryotic and prokaryotic microorganisms. Notably, it has not been previously reported in prokaryotes. The coexistence of β- and ζ-CAs in some microorganisms is also a novel finding as well. Also, our analysis identified several CA proteins with 6-14 amino acid intervals between histidine and cysteine in the second highly conserved motif, which can be classified as the novel ζ-CA subfamily members that emerged under the Zn deficiency of aquatic ecosystems and selection pressure in these environments. There is also a possibility that the achieved results are rooted in the contamination of samples from the environmental microbiome genome with genomes of diatom species and the occurrence of errors was observed in the DNA sequencing outcomes. Combining of all results from evolutionary analysis to quality control of ζ-CA DNA sequences is the incentive motivation to explore more the hidden aspects of ζ-CAs.

In Silico and Experimental Studies on the Effect of α3 and α5 Deletion on the Biochemical Properties of Bacillus thermocatenulatus Lipase

To investigate the effect of α3 and α5 helices on the biochemical characterization of Bacillus thermocatenulatus lipase (BTL2), both helices were deleted from native BTL2 lipase. After structural modeling and characterization, the truncated btl2 gene (Δbtl2) was cloned into E. coli BL21 under the control of the T7 promoter. After cultivation and induction of the recombinant bacteria, the Δα3α5 lipase was purified by Ni-NTA column chromatography. Next, the biochemical properties of the Δα3α5 lipase were compared with the previously expressed and purified native lipase. In the presence of the substrate tributyrin (C4), the maximum activity of native and Δα3α5 lipase was 9360 and 5000 U/mg, respectively. The deletion changed the substrate specificity from tributyrin (C4) to tricaprylin (C8) substrate. Native and Δα3α5 lipase showed similar activity patterns at all temperatures and pH values, with the activity of Δα3α5 lipase being approximately 20% lower than native lipase. Triton X100 increased the activity of native and Δα3α5 lipases by 2.1- and 2.5-fold, respectively.

Management, control, and decision making in unexpected recurrent venous thromboembolism in COVID-19: a case report

BACKGROUND

Coronavirus disease 2019 was spread worldwide, as a pandemic, from December 2019. Venous thromboembolism events can inflict patients with coronavirus disease 2019 during the hospitalization or convalescent period. Therefore, monitoring of these patients, in terms of venous thromboembolism events signs and symptoms, and timely management of antithrombotic agents are of great importance.

CASE REPORT

A 45-year-old Iranian man, who is the first author of this case report, was infected by severe acute respiratory syndrome coronavirus 2 and displayed the typical signs and symptoms of coronavirus disease 2019. Although reverse transcription polymerase chain reaction for coronavirus disease 2019, and specific immunoglobulin M and immunoglobulin G against severe acute respiratory syndrome coronavirus 2, were negative at first, chest computed tomography scan showed the characteristic pattern of lung involvement of a coronavirus disease 2019 infection including bilateral and multilobar ground-glass opacities. At that time, there were no signs or symptoms of deep-vein thrombosis or pulmonary thromboembolism, so these were not investigated. About 30 hours after hospital discharge, the patient presented back to the hospital with acute-onset chest pain. We instantly tested his blood for D-dimer, and sent him to take a Doppler sonography of his lower legs and a chest computed tomography angiography in search of pulmonary thromboembolism and deep-vein thrombosis. Although we could confirm pulmonary thromboembolism with computed tomography angiography in our patient, there were no signs or symptoms of venous thromboembolism in his lower legs, and color Doppler sonography of lower limbs was normal. So, the patient was treated with rivaroxaban as an antithrombotic agent. After some days, he was discharged in good condition. About 1 month later, he was referred to our hospital because of left lower limb edema. Although he was under antithrombotic therapy, color Doppler sonography of lower limbs revealed acute deep-vein thrombosis of the left leg. Hence, we decided to shift antithrombotic therapy from rivaroxaban to warfarin, as it is more potent than rivaroxaban in recurrent venous thromboembolism and when taking new oral anticoagulants. Unlike rivaroxaban, which needs no blood test to monitor its efficacy but has a warning for signs and symptoms of bleeding, warfarin therapy must be monitored carefully by regular blood tests for prothrombin time and international normalized ratio to maintain them in the therapeutic range. The patient was informed about the bleeding cautions, and required regular check of prothrombin time and international normalized ratio to maintain them in the proper and advised range of treatment (international normalized ratio therapeutic range 2-3).

CONCLUSION

In the case of unexpected recurrent venous thromboembolism in coronavirus disease 2019, especially when patients are taking rivaroxaban or other new oral anticoagulants, such drugs should be substituted by warfarin, with routine follow-up, to maintain the value of prothrombin time and international normalized ratio within the therapeutic range.

Electrospun Nanofibrous Scaffolds of Polycaprolactone/Gelatin Reinforced with Layered Double Hydroxide Nanoclay for Nerve Tissue Engineering Applications

Nerve tissue engineering (NTE) is an effective approach for repairing damaged nerve tissue. In this regard, nanoparticle-incorporated electrospun scaffolds have aroused a great deal of interest in NTE applications. In this study, layered double hydroxide (LDH)-incorporated polycaprolactone (PCL)/gelatin (Gel) nanofibrous scaffolds were fabricated by an electrospinning technique. The physicochemical, mechanical, and biological properties of the scaffolds were examined. Also, the phase identification, morphology, and elemental composition were studied using X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, respectively. The results revealed that the inclusion of LDH nanoparticles into the PCL/Gel scaffold has improved its mechanical strength and elongation at the break, while the degradation rate was enhanced in comparison with the pure PCL/Gel mat. The LDH-enriched electrospun PCL/Gel scaffolds exhibited a considerable impact on cell attachment and proliferation. The gene expression results showed that the neuron-specific (γγ) enolase (NSE) gene expression was significantly decreased in the scaffolds containing 1 and 10 wt % LDH compared to the scaffold without LDH, whereas in the scaffold with 0.1 wt % LDH, a slight increase in expression was observed. It can be deduced that electrospun PCL/Gel scaffolds containing LDH with optimum concentration can be a promising candidate for nerve tissue engineering applications.

Investigation of promoter methylation patterns association with genes expression profile of ISL1, MGMT and DMNT3b in tissue of breast cancer patients

BACKGROUND AND OBJECTIVES

Cancer initiation and progression could influenced by both genetic and epigenetic events revealing of the overlap between epigenetic and genetic alteration can give important insights into cancer biology.

METHODS AND RESULTS

In this experiment ISL1, MGMT, DMNT3b genes were candidate to investigate both methylation status and expression profile by using methylation-specific PCR and real time PCR in 40 breast cancer patients, respectively, also we have assessed relation of the promoter methylation status and expression variation of the target genes. The mean level of methylation of ISL1 and MGMT in tumor tissues were significantly greater than normal tissues. In Contrast, DMNT3b gene was showed lower mean level of methylation in tumor tissue compared to normal tissues, however, this was not statistically significant. Relative expression analysis was displayed a significant reduction in expression level of ISL1 and MGMT in tumor tissues. Furthermore, there was a meaningful association between down expression of ISL1 with histological grade, Her2 and ER status. Moreover, MGMT down expression was significantly associated with tumor sizes. Any remarkable relation was not observed between DMNT3b expression level and clinic pathological features. At the end, significant relation between methylation status and expression level has been revealed.

CONCLUSIONS

In this study all observed results were exactly in line with the results were obtained from articles which were based on the methylation research and illustrate that the real-time PCR and methylation methods are in correlated with each other, furthermore, selected genes are capable to use as a potential biomarkers, however, more research on extended cases are needed.

Betanin purification from red beetroots and evaluation of its anti-oxidant and anti-inflammatory activity on LPS-activated microglial cells

Microglial activation can release free radicals and various pro-inflammatory cytokines, which implicates the progress of a neurodegenerative disease. Therefore suppression of microglial activation can be an appropriate strategy for combating neurodegenerative diseases. Betanin is a red food dye that acts as free radical scavenger and can be a promising candidate for this purpose. In this study, purification of betanin from red beetroots was carried out by normal phase colum chromatography, yielding 500 mg of betanin from 100 g of red beetroot. The purified betanin was evaluated by TLC, UV-visible, HPLC, ESI-MASS, FT-IR spectroscopy. Investigation on the inhibitory effect of betanin on activated microglia was performed using primary microglial culture. The results showed that betanin significantly inhibited lipopolysaccharide induced microglial function including the production of nitric oxide free radicals, reactive oxygen species, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-1 beta (IL-1β). Moreover, betanin modulated mitochondrial membrane potential, lysosomal membrane permeabilization and adenosine triphosphate. We further investigated the interaction of betanin with TNF-α, IL-6 and Nitric oxide synthase (iNOS or NOS2) using in silico molecular docking analysis. The docking results demonstrated that betanin have significant negative binding energy against active sites of TNF-α, IL-6 and iNOS.

Analysis of transcriptional responses in root tissue of bread wheat landrace (Triticum aestivum L.) reveals drought avoidance mechanisms under water scarcity

In this study, high-throughput sequencing (RNA-Seq) was utilized to evaluate differential expression of transcripts and their related genes involved in response to terminal drought in root tissues of bread wheat landrace (L-82) and drought-sensitive genotype (Marvdasht). Subsets of 460 differentially expressed genes (DEGs) in drought-tolerant genotype and 236 in drought-sensitive genotype were distinguished and functionally annotated with 105 gene ontology (GO) terms and 77 metabolic pathways. Transcriptome profiling of drought-resistant genotype “L-82” showed up-regulation of genes mostly involved in Oxidation-reduction process, secondary metabolite biosynthesis, abiotic stress response, transferase activity and heat shock proteins. On the other hand, down-regulated genes mostly involved in signaling, oxidation-reduction process, secondary metabolite biosynthesis, auxin-responsive protein and lipid metabolism. We hypothesized that the drought tolerance in “L-82” was a result of avoidance strategies. Up-regulation of genes related to the deeper root system and adequate hydraulic characteristics to allow water uptake under water scarcity confirms our hypothesis. The transcriptomic sequences generated in this study provide information about mechanisms of acclimation to drought in the selected bread wheat landrace, “L-82”, and will help us to unravel the mechanisms underlying the ability of crops to reproduce and keep its productivity even under drought stress.

Development of a bifunctional xylanase-cellulase chimera with enhanced activity on rice and barley straws using a modular xylanase and an endoglucanase procured from camel rumen metagenome

The camel rumen metagenome is an untapped source of glycoside hydrolases. In this study, novel genes encoding for a modular xylanase (XylC) and a cellulase (CelC) were isolated from a camel rumen metagenome and expressed in Escherichia coli BL21 (DE3). XylC with xylanase (Xyn), CBM, and carbohydrate esterase (CE) domains was characterized as a β-1,4-endoxylanase with remarkable catalytic activity on oat-spelt xylan (K cat = 2919 ± 57 s-1). The implication of XylC's modular structure in its high catalytic activity was analyzed by truncation and fusion construction with CelC. The resulting fusions including Cel-CBM, Cel-CBM-CE, and Xyn-CBM-Cel showed remarkable enhancement in CMCase activity with K cat values of 742 ± 12, 1289 ± 34.5, and 2799 ± 51 s-1 compared to CelC with a K cat of 422 ± 3.5 s-1. It was also shown that the bifunctional Xyn-CBM-Cel with synergistic xylanase/cellulase activities was more efficient than XylC and CelC in hydrolysis of rice and barley straws.