Pantothenate Kinase Research Articles

NINJ1 regulates ferroptosis via xCT antiporter interaction and CoA modulation.

Ninjurin-1 (NINJ1), initially identified as a stress-induced protein in neurons, recently emerged as a key mediator of plasma membrane rupture (PMR) during apoptosis, necrosis, and pyroptosis. However, its involvement in ferroptosis is less well elucidated. Here, we demonstrate that NINJ1 also plays a crucial role in ferroptosis, but through a distinct mechanism. NINJ1 knockdown significantly protected cancer cells against ferroptosis induced only by xCT inhibitors but no other classes of ferroptosis-inducing compounds (FINs). Glycine, known to inhibit canonical NINJ1-mediated membrane rupture in other cell deaths, had no impact on ferroptosis. A compound screen revealed that the ferroptosis protective effect caused by NINJ1 knockdown can be abolished by pantothenate kinase inhibitor (PANKi), buthionine sulfoximine (BSO), and diethylmaleate (DEM). These results suggest that this ferroptosis protection is mediated via Coenzyme A (CoA) and glutathione (GSH), both of which were found to be elevated upon NINJ1 knockdown. Furthermore, we discovered that NINJ1 interacts with the xCT antiporter, which is responsible for cystine uptake for the biosynthesis of CoA and GSH. The removal of NINJ1 increased xCT levels and stability, enhancing cystine uptake and thereby providing protection against ferroptosis. Conversely, NINJ1 overexpression reduced xCT levels and sensitized ferroptosis. These findings reveal that NINJ1 regulates ferroptosis via a non-canonical mechanism, distinct from other regulated cell deaths.

KINOME-WIDE SYNTHETIC LETHAL SCREEN IDENTIfiES PANK4 AS A MODULATOR OF TEMOZOLOMIDE RESISTANCE IN GLIOBLASTOMA

Abstract AIMS Temozolomide (TMZ) represents the cornerstone of glioblastoma (GBM) therapy. However, acquisition of resistance limits its therapeutic potential. The human kinome is an undisputable source of druggable targets, still, current knowledge remains confined to a limited fraction of it, with a multitude of under-investigated proteins yet to be characterised. We aimed to uncover synthetic lethal partners of TMZ in GBM that could enhance the effect of TMZ, thus improving TMZ therapy response. METHOD A kinome-wide RNAi screen was performed in a TMZ-resistant GBM cell model. A panel of several TMZ-resistant and patient-derived GBM cell lines was implemented for in vitro validation of our findings through several phenotypic assays. In vivo TMZ-resistant GBM xenografts and immunohistochemical (IHC) analysis of IDH- wildtype GBM specimens were employed to assess the clinical relevance of our findings. Tandem Mass Tag (TMT)-based quantitative proteomic studies were undertaken to elucidate the underlying mechanisms. RESULTS Following a kinome-wide RNAi screen, pantothenate kinase 4 (PANK4) was uncovered as a modulator of TMZ resistance in GBM. Validation of PANK4 across various TMZ-resistant GBM cell models, patient-derived GBM cell lines, tissue samples, as well as in vivo studies, corroborated the potential translational significance of these findings. Moreover, PANK4 expression is induced during TMZ treatment, and its expression is associated with a worse clinical outcome. A Tandem Mass Tag (TMT)-based quantitative proteomic approach revealed that PANK4 abrogation leads to a significant downregulation of numerous proteins with central roles in cellular detoxification and cellular response to oxidative stress. Mechanistically, as cells undergo genotoxic stress during TMZ exposure, PANK4 depletion represents a crucial event that can lead to accumulation of intracellular reactive oxygen species (ROS) and subsequent cell death. CONCLUSION Our study provides novel insights into chemoresistance in GBM and unveils a previously unreported role for PANK4 in mediating therapeutic resistance to TMZ in GBM.

Intrathecal baclofen therapy as treatment for spasticity and dystonia: Review of cases in a pediatric palliative care unit

IntroductionPatients managed in the Pediatric Palliative Care Integral Unit (PPCIU) have serious neurological conditions that involve significant damage at central nervous system level. The movement disorder is a very common clinical problem and for the patients where an adequate control of muscle tone is not achieved with usual techniques or drugs, intrathecal baclofen therapy (IBT) should be considered. Materials and methodsDescriptive retrospective study based on the review of clinical records of patients who received IBT being followed by the PPCIU of Madrid Autonomous Region in the timeframe between September 2012 and February 2021. ResultsIBT was implanted in 8 patients affected by infantile cerebral palsy (ICP) with a Gross Motor Function Scale (GMFCS) IV–V, 3 patients was a Pantothenate kinase deficit-associated neurodegeneration (PKAN), 2 had Acquired Brain Damage, and the remaining 3 had, respectively, 2 glutaric aciduria type I (GA-1), and poly-malformative syndrome. In all patients we observed a period of clinical stability after IBT, we call this period “honeymoon”. Two patients died while in the honeymoon period, at 24.9 and 19.6 months from implantation of the pump; the median of duration of the honeymoon period in the remaining 14 was 14.4 months (IQ: 8.3–25.8). ConclusionsIBT was not only used in patients with non-progressive diseases, but also in the group of patients with neurodegenerative or progressive diseases. In all of them, after implantation of the device, we have objectified a period of clinical stability and a better control of muscle tone disorders.

Decreased PANK1 expression in kidney renal clear cell carcinoma: impact on cell apoptosis, invasion, migration, and epithelial-mesenchymal transition

ObjectiveTo investigate pantothenate kinases 1 (PANK1) expression in kidney renal clear cell carcinoma (KIRC) tissues, analyze its correlation with clinicopathological features and prognosis, and explore its impact on invasion, migration, and apoptosis in KIRC cells.MethodsGEPIA (gene expression profiling interactive analysis), UALCAN and LinkedOmics, were employed to analyze PANK1 expression in KIRC tissues and its correlation with clinical characteristics. Comparative analyses were performed between KIRC (Caki-1 and 786-O) and noncancerous renal cells (HK-2 and RPTEC). Transfection with PANK1 activation particles was conducted, followed by Wound healing, Transwell assay, Annexin V-fluorescein isothiocyanate/propidium iodide (Annexin V-FITC/PI) staining, quantitative reverse-transcription polymerase chain reaction (qRT-PCR), and Western blotting.ResultsPANK1 was down-regulated in KIRC tissues and cells compared to normal tissues and noncancerous cells. Correlation analyses linked PANK1 expression with clinicopathological features in KIRC, with high PANK1 expression associated with a favorable outcome. High PANK1 expression correlated positively with E-cadherin (CDH1), tight junction protein 1 (TJP1), Fas cell surface death receptor (FAS), caspase-8 (CASP8), and CASP9, while showing a negative correlation with vimentin (VIM), snail family transcriptional repressor 1 (SNAIL1), twist family BHLH transcription factor 1 (TWIST1), and TWIST2. PANK1 overexpression increased CDH1, TJP1, FAS, CASP8, and CASP9 while downregulating SNAIL1, VIM, TWIST1, and TWIST2, inhibiting invasion and migration, and promoting apoptosis in KIRC cells.ConclusionPANK1 down-regulation in KIRC tissues correlated with clinicopathological features and prognosis. Its overexpression modulated epithelial-mesenchymal transition (EMT)-related gene, inhibited invasion, promoted apoptosis in KIRC cells, highlighting its role in disease progression and therapeutic potential.

Development of Brain Penetrant Pyridazine Pantothenate Kinase Activators.

Conversion of pantothenate to phosphopantothenate in humans is the first dedicated step in the coenzyme A (CoA) biosynthesis pathway and is mediated by four isoforms of pantothenate kinase. These enzymes are allosterically regulated by acyl-CoA levels, which control the rate of CoA biosynthesis. Small molecule activators of the PANK enzymes that overcome feedback suppression increase CoA levels in cultured cells and animals and have shown great potential for the treatment of pantothenate kinase-associated neurodegeneration and propionic acidemias. In this study, we detail the further optimization of PANK pyridazine activators using structure-guided design and focus on the cellular CoA activation potential, metabolic stability, and solubility as the primary drivers of the structure-activity relationship. These studies led to the prioritization of three late-stage preclinical lead PANK modulators with improved pharmacokinetic profiles and the ability to substantially increase brain CoA levels. Compound 22 (BBP-671) eventually advanced into clinical testing for the treatment of PKAN and propionic acidemia.

SGLT2 inhibitors activate pantothenate kinase in the human heart.

Inhibitors of sodium glucose cotransporter-2 (SGLT2i) demonstrate strong symptomatic and mortality benefits in the treatment of heart failure but appear to do so independently of SGLT2. The relevant pharmacologic target of SGLT2i remains unclear. We show here that SGLT2i directly activate pantothenate kinase 1 (PANK1), the rate-limiting enzyme that initiates the conversion of pantothenate (vitamin B5) to coenzyme-A (CoA), an obligate co-factor for all major pathways of fuel use in the heart. Using stable-isotope infusion studies, we show that SGLT2i promote pantothenate consumption, activate CoA synthesis, rescue decreased levels of CoA in human failing hearts, and broadly stimulate fuel use in ex vivo perfused human cardiac blocks from patients with heart failure. Furthermore, we show that SGLT2i bind to PANK1 directly at physiological concentrations and promote PANK1 enzymatic activity in assays with purified components. Novel in silico dynamic modeling identified the site of SGLT2i binding on PANK1 and indicated a mechanism of activation involving prevention of allosteric inhibition of PANK1 by acyl-CoA species. Finally, we show that inhibition of PANK1 prevents SGLT2i-mediated increased contractility of isolated adult human cardiomyocytes. In summary, we demonstrate robust and specific off-target activation of PANK1 by SGLT2i, promoting CoA synthesis and efficient fuel use in human hearts, providing a likely explanation for the remarkable clinical benefits of SGLT2i.

Pantothenate kinase: A promising therapeutic target against pathogenic Clostridium species

Current treatment of clostridial infections includes broad-spectrum antibiotics and antitoxins, yet antitoxins are ineffective against all Clostridium species. Moreover, rising antimicrobial resistance (AMR) threatens treatment effectiveness and public health. This study therefore aimed to discover a common drug target for four pathogenic clostridial species, Clostridium botulinum, C. difficile, C. tetani, and C. perfringens through an in-silico core genomic approach. Using four reference genomes of C. botulinum, C. difficile, C. tetani, and C. perfringens, we identified 1484 core genomic proteins (371/genome) and screened them for potential drug targets. Through a subtractive approach, four core proteins were finally identified as drug targets, represented by type III pantothenate kinase (CoaX) and, selected for further analyses. Interestingly, the CoaX is involved in the phosphorylation of pantothenate (vitamin B5), which is a critical precursor for coenzyme A (CoA) biosynthesis. Investigation of druggability analysis on the identified drug target reinforces CoaX as a promising novel drug target for the selected Clostridium species. During the molecular screening of 1201 compounds, a known agonist drug compound (Vibegron) showed strong inhibitory activity against targeted clostridial CoaX. Additionally, we identified tazobactam, a beta-lactamase inhibitor, as effective against the newly proposed target, CoaX. Therefore, identifying CoaX as a single drug target effective against all four clostridial pathogens presents a valuable opportunity to develop a cost-effective treatment for multispecies clostridial infections.

Citrate synthase variants improve yield of acetyl-CoA derived 3-hydroxybutyrate in Escherichia coli

BackgroundThe microbial chiral product (R)-3-hydroxybutyrate (3-HB) is a gateway to several industrial and medical compounds. Acetyl-CoA is the key precursor for 3-HB, and several native pathways compete with 3-HB production. The principal competing pathway in wild-type Escherichia coli for acetyl-CoA is mediated by citrate synthase (coded by gltA), which directs over 60% of the acetyl-CoA into the tricarboxylic acid cycle. Eliminating citrate synthase activity (deletion of gltA) prevents growth on glucose as the sole carbon source. In this study, an alternative approach is used to generate an increased yield of 3-HB: citrate synthase activity is reduced but not eliminated by targeted substitutions in the chromosomally expressed enzyme.ResultsFive E. coli GltA variants were examined for 3-HB production via heterologous overexpression of a thiolase (phaA) and NADPH-dependent acetoacetyl-CoA reductase (phaB) from Cupriavidus necator. In shake flask studies, four variants showed nearly 5-fold greater 3-HB yield compared to the wild-type, although pyruvate accumulated. Overexpression of either native thioesterases TesB or YciA eliminated pyruvate formation, but diverted acetyl-CoA towards acetate formation. Overexpression of pantothenate kinase similarly decreased pyruvate formation but did not improve 3-HB yield. Controlled batch studies at the 1.25 L scale demonstrated that the GltA[A267T] variant produced the greatest 3-HB titer of 4.9 g/L with a yield of 0.17 g/g. In a phosphate-starved repeated batch process, E. coli ldhA poxB pta-ackA gltA::gltA[A267T] generated 15.9 g/L 3-HB (effective concentration of 21.3 g/L with dilution) with yield of 0.16 g/g from glucose as the sole carbon source.ConclusionsThis study demonstrates that GltA variants offer a means to affect the generation of acetyl-CoA derived products. This approach should benefit a wide range of acetyl-CoA derived biochemical products in E. coli and other microbes. Enhancing substrate affinity of the introduced pathway genes like thiolase towards acetyl-CoA will likely further increase the flux towards 3-HB while reducing pyruvate and acetate accumulation.

HLH-30/TFEB rewires the chaperone network to promote proteostasis under conditions of Coenzyme A and Iron-Sulfur Cluster Deficiency.

The maintenance of a properly folded proteome is critical for cellular function and organismal health, and its age-dependent collapse is associated with a wide range of diseases. Here, we find that despite the central role of Coenzyme A as a molecular cofactor in hundreds of cellular reactions, limiting Coenzyme A levels in C. elegans and in human cells, by inhibiting the conserved pantothenate kinase, promotes proteostasis. Impairment of the cytosolic iron-sulfur clusters formation pathway, which depends on Coenzyme A, similarly promotes proteostasis and acts in the same pathway. Proteostasis improvement by Coenzyme A/iron-sulfur cluster deficiencies are dependent on the conserved HLH-30/TFEB transcription factor. Strikingly, under these conditions, HLH-30 promotes proteostasis by potentiating the expression of select chaperone genes providing a chaperone-mediated proteostasis shield, rather than by its established role as an autophagy and lysosome biogenesis promoting factor. This reflects the versatile nature of this conserved transcription factor, that can transcriptionally activate a wide range of protein quality control mechanisms, including chaperones and stress response genes alongside autophagy and lysosome biogenesis genes. These results highlight TFEB as a key proteostasis-promoting transcription factor and underscore it and its upstream regulators as potential therapeutic targets in proteostasis-related diseases.

Use of acetate as substrate for sustainable production of homoserine and threonine by Escherichia coli W3110: A modular metabolic engineering approach

Acetate, a promising yet underutilized carbon source for biological production, was explored for the efficient production of homoserine and threonine in Escherichia coli W. A modular metabolic engineering approach revealed the crucial roles of both acetate assimilation pathways (AckA/Pta and Acs), optimized TCA cycle flux and glyoxylate shunt activity, and enhanced CoA availability, mediated by increased pantothenate kinase activity, for efficient homoserine production. The engineered strain W–H22/pM2/pR1P exhibited a high acetate assimilation rate (5.47 mmol/g cell/h) and produced 44.1 g/L homoserine in 52 h with a 53% theoretical yield (0.18 mol/mol) in fed-batch fermentation. Similarly, strain W–H31/pM2/pR1P achieved 45.8 g/L threonine in 52 h with a 65% yield (0.22 mol/mol). These results represent the highest reported levels of amino acid production using acetate, highlighting its potential as a valuable and sustainable feedstock for biomanufacturing.

The role of pantothenic acid in alleviating hypoxia-induced liver injury of sub-adult grass carp (Ctenopharyngodon idellus): Possible mechanisms and implication

In aquaculture, hypoxia poses a significant threat to fish growth and survival. Despite this, there is limited research on the impact of pantothenic acid (PA) in enhancing the anti-hypoxia stress capability of fish. The primary objective of this study was to explore the effects and potential mechanisms of PA in alleviating hypoxia-induced liver injury in sub-adult grass carp. To achieve this, six experimental diets containing varying levels of PA (0.08, 11.95, 24.95, 37.95, 50.95, and 63.95 mg/kg) were formulated and administered to grass carp (initial weight 696.22 ± 2.45 g) for 63 days. Following the dietary intervention, the fish were segregated into hypoxia and control groups and treated for 96 h. The findings revealed that optimal PA levels could enhance the growth performance of sub-adult grass carp and ameliorate the adverse impacts of hypoxia. First, optimal PA levels reduced serum levels of glutamate-oxaloacetate transaminase (GOT), glutamate-pyruvate transaminase (GPT), and lactate dehydrogenase (LDH), as well as mitigated hepatocyte vacuolization, improved liver and mitochondrial morphology, thereby alleviating hypoxia-induced liver injury. Furthermore, optimal PA levels were associated with increased contents of serum cortisol, glucose, liver glycogen, pyruvate, and the activities of Pantothenate kinase 2 (PanK2) and coenzyme A (CoA), while liver lactate content and LDH activity were reduced, indicating improvements in energy metabolism and PA utilization, potentially mediated by the down-regulation of hypoxia-inducible factor-1α (HIF-1α) mRNA level. Moreover, optimal PA levels decreased reactive oxygen species (ROS) and malondialdehyde (MDA) levels, enhanced liver antioxidant capacity, down-regulated autophagy-related gene mRNA levels, and up-regulated autophagy receptor protein 62 (p62) protein level, suggesting a reduction in oxidative damage and autophagy. Finally, a rise in levels of mitochondrial quality control-related mRNAs such as mitofusin 1/2 (MFN1/2), dynamin-related protein-1 (DRP-1), and nuclear respiratory factor 1/2 (Nrf-1/2) was observed, together with increment in the protein levels of PTEN induced putative kinase 1 (PINK1), BCL-2 interacting protein 3 (BNIP3) and FUN14 domain-containing protein 1 (FUNDC1). These alterations hinted at the role of PA in preserving mitochondrial homeostasis. In conclusion, PA exhibited a protective role against hypoxia-induced liver injury by enhancing liver energy metabolism, bolstering antioxidant defenses, suppressing autophagy, and maintaining mitochondrial homeostasis. Through an assessment of percentage weight gain (PWG) and liver ROS level, the requirements of PA for promoting growth and resilience to hypoxia-induced liver injury in sub-adult grass carp were determined to be 37.44 mg/kg and 42.57 mg/kg, respectively.

Pantothenate kinase-associated neurodegeneration (PKAN) a rare neurodegenerative disease-Two case reports

Neurodegeneration with brain iron accumulation (NBIA) is a subtype of inherited metabolic disorders. It includes pantothenate kinase-associated neurodegeneration (PKAN), which is a rare autosomal recessive disorder caused by the mutation of pantothenate kinase 2-gene (PANK2). It affects the deep grey matter nuclei causing progressive extra pyramidal motor impairment. We present two cases who are presented in our department with walking difficulty, dystonia and dysarthria. MRI of brain (T2) showed- hyper intensity of the basal ganglia with the classic eye-of-the-tiger sign and one child's genetic study revealed mutation in PANK2 gene. We managed them with anti dystonic drugs along with iron chelating agent. J Bangladesh Coll Phys Surg 2024; 42: 209-213

MiR-103-5p deficiency suppresses lipid accumulation via upregulating PLSCR4 and its host gene PANK3 in goat mammary epithelial cells

Lipids are intimately related to the unique flavor and nutritional values of goat milk. MicroRNAs (miRNA) participate in the regulation of various biological functions, including the synthesis and degradation of lipids. Several studies have shown that miR-103 is involved in the regulation of lipid metabolism, however, the molecular mechanism by which miR-103 regulates lipid metabolism in goat mammary gland is poorly understood. In this study, miR-103 was knocked out in goat mammary epithelial cells (GMECs) by CRISPR/Cas9, and the accumulation of lipid droplets, triglycerides, and cholesterol in the cells was suppressed subsequently. Overexpression or knockdown of miR-103-5p and miR-103-3p in GMECs revealed that it was miR-103-5p that promoted lipid accumulation but not miR-103-3p. In addition, Pantothenate Kinase 3 (PANK3), the host gene of miR-103, and Phospholipid Scramblase 4 (PLSCR4) were identified as the target genes of miR-103-5p by dual fluorescein and miRNA pulldown. Furthermore, we identified that cellular lipid levels were negatively regulated by PANK3 and PLSCR4. Lastly, in miR-103 knockout GMECs, the knockdown of PANK and PLSCR4 rescued the lipid accumulation. These findings suggest that miR-103-5p promotes lipid accumulation by targeting PLSCR4 and the host gene PANK3 in GMECs, providing new insights for the regulation of goat milk lipids via miRNAs.

Expression and Prognostic Role of PANK1 in Glioma.

Malignant gliomas are the most common type of primary malignant brain tumors. Pantothenate kinase 1 (PANK1) mRNA is highly expressed in several metabolic processes, implying that PANK1 plays a potential role in metabolic programming in cancers. However, the role of PANK1 in glioma has not been fully explored. Public datasets (The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), Gravendeel and Rembrandt) and validation cohort were used to explore the expression of PANK1 in glioma tissues. Kaplan-Meier and Cox regression analyses were used to explore the relationship between PANK1 and prognosis in glioma. Cell proliferation and invasion were determined using Cell Counting Kit-8 (CCK8) and transwell invasion in vitro assays. Analysis using the four public datasets and the validation cohort showed that PANK1 expression was significantly downregulated in glioma tissues compared with non-tumor tissues (P<0.01). PANK1 expression was negatively correlated with World Health Organization (WHO) grade, 1p/19q non-codeletion and isocitric dehydrogenase 1/2 (IDH1/2) wildtype. Furthermore, high expression of PANK1 was correlated with significantly better prognosis of glioma patients compared to patients with low expression of PANK1 (all P<0.01 in the four datasets). Besides, both lower-grade glioma (LGG) and glioblastoma multiform (GBM) patients with high expression of PANK1 had a significantly better prognosis than those with low expression of PANK1 in TCGA, Gravendeel and Rembrandt datasets (all P <0.01). Multivariate Cox regression analysis revealed that low PANK1 expression was an independent risk factor associated with a worse prognosis of glioma patients. Moreover, overexpression of PANK1 significantly inhibited the proliferation and invasion of U87 and U251 cells. PANK1 expression is downregulated in glioma tissues and is a novel prognostic biomarker in glioma patients.

Kinome-Wide Synthetic Lethal Screen Identifies PANK4 as a Modulator of Temozolomide Resistance in Glioblastoma.

Temozolomide (TMZ) represents the cornerstone of therapy for glioblastoma (GBM). However, acquisition of resistance limits its therapeutic potential. The human kinome is an undisputable source of druggable targets, still, current knowledge remains confined to a limited fraction of it, with a multitude of under-investigated proteins yet to be characterized. Here, following a kinome-wide RNAi screen, pantothenate kinase 4 (PANK4) isuncovered as a modulator of TMZ resistance in GBM. Validation of PANK4 across variousTMZ-resistant GBM cell models, patient-derivedGBM cell lines, tissue samples, as well as in vivo studies, corroborates the potential translational significance of these findings. Moreover, PANK4 expression is induced during TMZ treatment, and its expression is associated with a worse clinical outcome. Furthermore, a Tandem Mass Tag (TMT)-based quantitative proteomic approach, reveals that PANK4 abrogation leads to a significant downregulation of a host of proteins with central roles in cellular detoxification and cellular response to oxidative stress. More specifically, as cells undergo genotoxic stress during TMZ exposure, PANK4 depletion represents a crucial event that can lead to accumulation of intracellular reactive oxygen species (ROS) and subsequent cell death. Collectively, a previously unreported role for PANK4 in mediating therapeutic resistance to TMZ in GBM is unveiled.

Synthesis, Antioxidant and Antituberculosis Evaluation of Eugenol Derivatives from Mannich Condensation

AbstractMannich bases are interesting class of molecules thanks to their various pharmacological properties. This paper presents the synthesis and characterization of eugenol derivatives following Mannich condensation. The in vitro antituberculosis activity of the synthesized derivatives was evaluated by the Resazurin microtiter assay (REMA). The 2,2′‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging and ferrous cation (FeCl2) chelating tests were used to estimate the antioxidant capacity. All eugenol Mannich bases inhibited the Mycobacterium tuberculosis (Mtb) H37Rv growing. Those of 2‐dimethylaminomethyl‐6‐methoxy‐4‐propenylphenol (1) and 2‐methoxy‐4‐propenyl‐6‐pyrrolidinylmethylphenol (4) were the most active at 10 μg/mL. Additionally, significant antioxidant profile was exhibited by the synthesized derivatives, especially for 2‐dicyclohexylaminomethyl‐6‐methoxy‐4‐propenylphenol (5) that showed an antiradical activity of EC50=20 μg/mL, twice as strong as that of eugenol precursor, and for 2‐methoxy‐6‐methylpiperazinylmethyl‐4‐propenylphenol (3) and compound 4, which were promising iron chelators with EC50 of 0.016 and 0.018 mg/mL, respectively, better than EDTA standard. The molecular docking experiments on two different antituberculosis receptors showed excellent binding affinity of compounds 4 and 5 into the active site of pantothenate kinase (PanK, type I), suggesting PanK as potential molecular target. These encouraging findings showed the importance of Mannich reaction for the development of antitubercular candidates and the improvement of natural products bioactivity.

In vitro and in silico exploration of newly synthesized triazolyl- isonicotinohydrazides as potent antitubercular agents

In the present study, we have reported the synthesis of novel isoniazid-triazole derivatives (4a-r), via the click chemistry approach. The synthesized isoniazid-triazole derivatives have potent in vitro antitubercular activity against the Mycobacterium tuberculosis (MTB) H37Rv strain. Among these compounds, 4b, 4f, 4g, 4j, 4k, 4m, 4o, 4p, and 4r were found to be the most active ones with a MIC value of 0.78 μg/mL. This activity is better than ciprofloxacin (MIC value = 1.56 μg/mL) and ethambutol (MIC value = 3.12 μg/mL). The compounds, 4a, 4c, 4d, 4e, 4h, 4i, 4l, and 4n have displayed activity equal to ciprofloxacin (MIC value = 1.56 μg/mL). The cytotoxicity of the active isoniazid-triazole derivatives was studied against RAW 264.7 cell line by MTT assay at 25 μg/mL concentration and no toxicity was observed. Moreover, in-vitro results were supported by in-silico studies with the known antitubercular target (PanK). The drug-likeness, density functional study, molecular docking, and molecular dynamics simulation studies of isoniazid-triazole derivatives validated the ability to form a stable complex with Pantothenate kinase (PanK), which will result in inhibiting the Pantothenate kinase (PanK). Therefore, the results obtained indicate that this class of compounds may offer candidates for future development, and positively provide drug alternatives for tuberculosis treatment.Communicated by Ramaswamy H. Sarma

Revealing the Mechanisms of Enhanced β-Farnesene Production in Yarrowia lipolytica through Metabolomics Analysis.

β-Farnesene is an advanced molecule with promising applications in agriculture, the cosmetics industry, pharmaceuticals, and bioenergy. To supplement the shortcomings of rational design in the development of high-producing β-farnesene strains, a Metabolic Pathway Design-Fermentation Test-Metabolomic Analysis-Target Mining experimental cycle was designed. In this study, by over-adding 20 different amino acids/nucleobases to induce fluctuations in the production of β-farnesene, the changes in intracellular metabolites in the β-farnesene titer-increased group were analyzed using non-targeted metabolomics. Differential metabolites that were detected in each experimental group were selected, and their metabolic pathways were located. Based on these differential metabolites, targeted strain gene editing and culture medium optimization were performed. The overexpression of the coenzyme A synthesis-related gene pantothenate kinase (PanK) and the addition of four mixed water-soluble vitamins in the culture medium increased the β-farnesene titer in the shake flask to 1054.8 mg/L, a 48.5% increase from the initial strain. In the subsequent fed-batch fermentation, the β-farnesene titer further reached 24.6 g/L. This work demonstrates the tremendous application value of metabolomics analysis for the development of industrial recombinant strains and the optimization of fermentation conditions.

Transcranial sonography in neurodegeneration with brain iron accumulation disorders

BackgroundTranscranial Sonography is a non-invasive technique that has been used as a diagnostic tool for a variety of neurodegenerative disorders. However, the utility and potential application of this technique in NBIA disorders is scarce and inconclusive. MethodsIn this cross-sectional retrospective case-control study, the echogenicity of Substantia Nigra (SN), Lentiform Nucleus (LN), and Diameter of the Third Ventricle (DTV) were assessed by TCS in genetically confirmed NBIA patients referring to the movement disorder clinic. The normal echogenicity area of SN was defined based on the 90th percentile of an age-and-gender-matched control group. NBIA patients underwent neurologic examination at each visit, but their brain magnetic resonance imaging and demographics were extracted from electronic records. ResultsThirty-five NBIA patients of four subtypes with a mean disease duration of 10.54 years and 35 controls were enrolled. The normally defined SN echogenicity in controls was 0.23 cm2. DTV and SN echogenicity areas were significantly higher in patients compared to the controls (P = 0.002 and < 0.001, respectively). Around 85% and 63% of the patients showed LN and SN hyperechogenicity at least on one side, respectively. Disease duration was positively correlated with DTV (r = 0.422, p = 0.015). Cases with Pantothenate Kinase Associated Neurodegeneration (n = 23) also had significantly higher DTV and SN echogenicity area compared to the controls. ConclusionDespite most NBIA patients displayed increased DVT and higher SN and LN hyperechogenicity than healthy controls, the discriminatory role of TCS on different NBIA subtypes remains to be determined.

Pantothenate Kinase Activation Restores Brain Coenzyme A in a Mouse Model of Pantothenate Kinase-Associated Neurodegeneration.

Pantothenate kinase-associated neurodegeneration (PKAN) is characterized by a motor disorder with combinations of dystonia, parkinsonism, and spasticity, leading to premature death. PKAN is caused by mutations in the PANK2 gene that result in loss or reduction of PANK2 protein function. PANK2 is one of three kinases that initiate and regulate coenzyme A biosynthesis from vitamin B5, and the ability of BBP-671, an allosteric activator of pantothenate kinases, to enter the brain and elevate coenzyme A was investigated. The metabolic stability, protein binding, and membrane permeability of BBP-671 all suggest that it has the physical properties required to cross the blood-brain barrier. BBP-671 was detected in plasma, liver, cerebrospinal fluid, and brain following oral administration in rodents, demonstrating the ability of BBP-671 to penetrate the brain. The pharmacokinetic and pharmacodynamic properties of orally administered BBP-671 evaluated in cannulated rats showed that coenzyme A (CoA) concentrations were elevated in blood, liver, and brain. BBP-671 elevation of whole-blood acetyl-CoA served as a peripheral pharmacodynamic marker and provided a suitable method to assess target engagement. BBP-671 treatment elevated brain coenzyme A concentrations and improved movement and body weight in a PKAN mouse model. Thus, BBP-671 crosses the blood-brain barrier to correct the brain CoA deficiency in a PKAN mouse model, resulting in improved locomotion and survival and providing a preclinical foundation for the development of BBP-671 as a potential treatment of PKAN. SIGNIFICANCE STATEMENT: The blood-brain barrier represents a major hurdle for drugs targeting brain metabolism. This work describes the pharmacokinetic/pharmacodynamic properties of BBP-671, a pantothenate kinase activator. BBP-671 crosses the blood-brain barrier to correct the neuron-specific coenzyme A (CoA) deficiency and improve motor function in a mouse model of pantothenate kinase-associated neurodegeneration. The central role of CoA and acetyl-CoA in intermediary metabolism suggests that pantothenate kinase activators may be useful in modifying neurological metabolic disorders.