👤 Bhavesh Pant

Biased agonism of the glucagon-like peptide-1/glucose-dependent insulinotropic polypeptide receptors (GLP-1R/GIPR) yields greater weight loss and better glycemic control than unbiased agonism in preclinical models. To evaluate whether biased agonism translates into improved efficacy for weight loss and glycemic control in clinical settings, we developed and characterized CT-388, a unimolecular peptide-based dual GLP-1R/GIPR agonist that is cAMP signal-biased at both receptors. In cell-based assays, CT-388 activated GLP-1R and GIPR with both having minimal receptor internalization vs their native ligands. CT-388 improved glycemic control in mice and monkeys, and reduced bodyweight, suppressed appetite, and improved metabolic dysfunction-associated steatohepatitis pathology in mice. In a phase 1, double-blind, randomized, placebo-controlled clinical study (NCT04838405) of CT-388 (subcutaneously administered single doses [0.5-7.5 mg] or 4 once-weekly doses [5-12 mg]) in otherwise healthy participants with overweight or obesity, CT-388 was generally well tolerated with a safety profile consistent with other incretin-based therapies; most treatment-emergent adverse events were mild or moderate. Glycemic parameters were improved during fasting conditions and an oral glucose tolerance test. The mean percent change in bodyweight from baseline to day 29 was -4.7% to -8.0% across CT-388 doses vs -0.5% with placebo. CT-388 pharmacokinetics supported once-weekly dosing. In conclusion, CT-388 demonstrated strong translatability from preclinical to clinical studies with consistent pharmacokinetics and pharmacodynamics across multiple species. In clinical settings, 4 weeks of CT-388 treatment produced clinically meaningful weight loss and improved glycemic control with favorable tolerability. These findings warrant further clinical evaluation of CT-388 for treating obesity and type 2 diabetes. Show less

The paraventricular hypothalamus (PVH) controls behavioral and physiologic processes, including appetite, social behavior, autonomic outflow, and pituitary hormone secretion. However, molecular markers for centrally projecting PVH neuron populations remain largely undefined, and a complete census of PVH cell types has not been established. Therefore, we performed extensive single-cell/nucleus RNA sequencing to catalog PVH neuron subtypes and multiplexed error-robust fluorescence in situ hybridization (MERFISH) to map them spatially. Our spatial transcriptomic atlas resolves 26 Sim1 Show less

Genetic variants near LYPLAL1 are associated with Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD) in humans, but their impact on LYPLAL1 function is unknown. We identified LYPLAL1 loss-of-function variants from UK BioBank (UKBB) whole-exome sequencing data that had AlphaMissense or GPN-MSA scores in the top 20% of LYPLAL1 variants for being disruptive. We aggregated these variants and carried out burden analysis for effects on MRI Proton Density-Fat Fraction (MRI-PDFF) and ICD-based MASLD in UKBB. Rare loss-of-function LYPLAL1 variants were associated with reduced MRI-PDFF and ICD diagnosed MASLD across sexes. We used CRISPR to knockout and overexpress LYPLAL1 in human hepatoma cells (HuH-7), measuring lipid content, lipid uptake/export, and changes in de novo lipogenesis and mitochondrial β-oxidation. LYPLAL1 subcellular localization was determined by overexpressing LYPLAL1-HA tagged protein. We purified GST tagged human LYPLAL1 protein and conducted in vitro tests for esterase and depalmitoylase activity. Knocking out LYPLAL1 reduced triglycerides biochemically as well as lipid intensity after oleic (18:1, n-9) acid treatment. LYPLAL1 KO cells had increased expression of PPARα and MLXIPL, increased mitochondrial β-oxidation, and reduced capacity to both import fatty acids (FAs) and export lipoproteins. Overexpression of LYPLAL1 increased lipid droplet accumulation and decreased PPARα and MLXIPL. LYPLAL1-HA is partly localized to mitochondria when treated with oleic acid. Biochemical analyses showed that LYPLAL1 has strong esterase activity but lacks depalmitoylase activity. Reduction of LYPLAL1 esterase function likely increases β-oxidation of FAs in mitochondria through PPARα and MLXIPL and decreases FA import to protect against lipid accumulation in human liver cancer cells. Together, our results indicate that LYPLAL1 loss-of-function protects against MASLD in Europeans and in vitro, LYPLAL1 is an esterase for short-chain substrates which is involved in the regulation of mitochondrial β-oxidation and uptake of fatty acids, influencing lipid accumulation in the liver. Show less

Glucagon-like peptide-1 receptor (GLP-1R) and glucose-dependent insulinotropic polypeptide receptor (GIPR) agonists have recently been shown to play a significant role in the treatment of diabetes and obesity. Better understanding of their signaling and mechanism of action could further improve their therapeutic effects. In the current study, we investigate the impact of biased cyclic AMP (cAMP) signaling of GLP-1R and GIPR, individually, as well as the combined effects of a unimolecular dually biased GLP-1R/GIPR agonist, CT-859, on glucose, food consumption, and body weight regulation. Our data demonstrate that biased agonism of either GLP-1R or GIPR leads to better glycemic regulation, greater food intake suppression, and weight loss. In addition, concerted biased activation of both GLP-1R and GIPR results in substantially higher efficacy. Activation of GLP-1R and GIPR with a combination of individually biased agonists or via a dually biased unimolecular approach with CT-859 may provide significant therapeutic advantages for the treatment of diabetes and obesity. Show less

Beef quality is critically determined by intramuscular fat (IMF) deposition. Retinoic acid (RA), the active metabolite of vitamin A, plays an essential regulatory role in IMF development. To systematically investigate RA-mediated regulation of IMF formation in cattle, we established a concentration gradient of RA supplementation and employed a systematic screening approach to identify the optimal dosage for modulating bovine intramuscular adipocytes (IMAs) proliferation and differentiation. Subsequently, leveraging integrated multi-omics approaches, we screened the key downstream molecular targets through which RA governs IMF biosynthesis, and clarified the potential regulatory mechanism of this target. Our experimental data establish that RA promotes the proliferation of IMAs through modulation of G1/S phase progression. Concurrently, RA enhances triglyceride biosynthesis in IMAs by activating PPARγ-mediated cell differentiation and LPL-mediated intracellular lipid accumulation. Integrated transcriptomics and metabonomics analyses identified FABP4, CD36, EBF2, LRP1 and CAV1 as key candidate genes involved in RA-mediated IMF production. Functional interrogation revealed that FABP4 knockdown markedly attenuated lipid accumulation in IMAs, a phenotype rescued through RA supplementation, confirming FABP4 as the critical effector mediating vitamin A's regulation of bovine IMF deposition. These results provide a new understanding of how nutritional factors affect beef quality at the molecular level. Show less

The interaction between stromal and tumor cells in tumor microenvironment is a crucial factor in Mantle cell lymphoma (MCL) progression and therapy resistance. We have identified a long non-coding RNA, CERS6-AS1, upregulated in MCL and associated with poor overall survival. CERS6-AS1 expression was elevated in primary MCL within stromal microenvironment and in a subset of MCL cells adhered to stromal layer. These stromal-adhered MCL-subsets exhibited cancer stem cell signatures than suspension counterparts. Mechanistically, we found that downregulating CERS6-AS1 in MCL reduced Fibroblast Growth Factor Receptor-1 (FGFR1), expression attributed to loss of its interaction with RNA-binding protein nucleolin. In addition, using in-silico approach, we have discovered a direct interaction between nucleolin and 5'UTR of FGFR1, thereby regulating FGFR1 transcript stability. We discovered a positive association of CERS6-AS1 with cancer stem cell signatures, and Wnt signaling. Building on these, we explored potential therapeutic strategies where combining nucleolin-targeting agent with FGFR1 inhibition significantly contributed to reversing cancer stem cell signatures and abrogated primary MCL cell growth on stromal layer. These findings provide mechanistic insights into regulatory network involving CERS6-AS1, nucleolin, and FGFR1 axis-associated crosstalk between tumor cells and stromal cell interaction and highlights therapeutic potential of targeting a non-coding RNA in MCL. Show less

FGFR alterations are reported across various malignancies and might act as oncogenic drivers in multiple histologies. Erdafitinib is an oral, selective pan-FGFR tyrosine kinase inhibitor with activity in FGFR-altered advanced urothelial carcinoma. We aimed to evaluate the safety and activity of erdafitinib in previously treated patients with FGFR-altered advanced solid tumours. The single-arm, phase 2 RAGNAR study was conducted at 156 investigative centres (hospitals or oncology practices that are qualified oncology study centres) across 15 countries. The study consisted of four cohorts based on tumour histology and patient age; the results reported in this Article are for the primary cohort of the study, defined as the Broad Panel Cohort, which was histology-agnostic. We recruited patients aged 12 years or older with advanced or metastatic tumours of any histology (except urothelial cancer) with predefined FGFR1-4 alterations (mutations or fusions according to local or central testing). Eligible patients had disease progression on at least one previous line of systemic therapy and no alternative standard therapy available to them, and an Eastern Cooperative Oncology Group performance status of 0-1 (or equivalent for adolescents aged 12-17 years). Patients received once-daily oral erdafitinib (8 mg/day with provision for pharmacodynamically guided up-titration to 9 mg/day) on a continuous 21-day cycle until disease progression or intolerable toxicity. The primary endpoint was objective response rate by independent review committee according to Response Evaluation Criteria In Solid Tumors (RECIST), version 1.1, or Response Assessment In Neuro-Oncology (RANO). The primary analysis was conducted on the treated population of the Broad Panel Cohort. This ongoing study is registered with ClinicalTrials.gov, number NCT04083976. Patients were recruited between Dec 5, 2019, and Feb 15, 2022. Of 217 patients treated with erdafitinib, 97 (45%) patients were female and 120 (55%) were male. The data cutoff was Aug 15, 2022. At a median follow-up of 17·9 months (IQR 13·6-23·9), an objective response was observed in 64 (30% [95% CI 24-36]) of 217 patients across 16 distinct tumour types. The most common grade 3 or higher treatment-emergent adverse events related to erdafitinib were stomatitis (25 [12%]), palmar-plantar erythrodysaesthesia syndrome (12 [6%]), and hyperphosphataemia (11 [5%]). The most commonly occurring serious treatment-related adverse events (grade 3 or higher) were stomatitis in four (2%) patients and diarrhoea in two (1%). There were no treatment-related deaths. RAGNAR results show clinical benefit for erdafitinib in the tumour-agnostic setting in patients with advanced solid tumours with susceptible FGFR alterations who have exhausted other treatment options. These results support the continued development of FGFR inhibitors in patients with advanced solid tumours. Janssen Research & Development. Show less

Hereditary Multiple Exostoses (HME), also known as Multiple Osteochondromas (MO) is a rare genetic disorder characterized by multiple benign cartilaginous bone tumors, which are caused by mutations in the genes for exostosin glycosyltransferase 1 (EXT1) and exostosin glycosyltransferase 2 (EXT2). The genetic defects have not been studied in the Saudi patients. We investigated mutation spectrum of EXT1 and EXT2 in 22 patients from 17 unrelated families. Genomic DNA was extracted from peripheral leucocytes. The coding regions and intron-exon boundaries of both EXT1 and EXT2 genes were screened for mutations by PCR-sequencing analysis. Gross deletions were analyzed by MLPA analysis. EXT1 mutations were detected in 6 families (35%) and 3 were novel mutations: c.739G > T (p. E247*), c.1319delG (p.R440Lfs*4), and c.1786delA (p.S596Afs*25). EXT2 mutations were detected in 7 families (41%) and 3 were novel mutations: c.541delG (p.D181Ifs*89), c.583delG (p.G195Vfs*75), and a gross deletion of approximately 10 kb including promoter and exon 1. Five patients from different families had no family history and carried de novo mutations (29%, 5/17). No EXT1 and EXT2 mutations were found in the remaining four families. In total, EXT1 and EXT2 mutations were found in 77% (13/17) of Saudi HME patients. EXT1 and EXT2 mutations contribute significantly to the pathogenesis of HME in the Saudi population. In contrast to high mutation rate in EXT 1 (65%) and low mutation rate in EXT2 (25%) in other populations, the frequency of EXT2 mutations are much higher (41%) and comparable to that of EXT1 among Saudi patients. De novo mutations are also common and the six novel EXT1/EXT2 mutations further expands the mutation spectrum of HME. Show less

Small RNA molecules (small RNAs), including small interfering RNAs (siRNAs), microRNAs (miRNAs), and piwi-interacting RNAs (piRNAs), have recently emerged as important regulators of gene expression at the post-transcriptional or translation level. Significant progress has recently been made utilizing small RNAs in elucidating the molecular mechanisms regulating spermatogenesis. Spermatogenesis is a complex process that involves the division and eventual differentiation of spermatogonial stem cells into mature spermatozoa. The process of spermatogenesis is composed of several phases: mitotic proliferation of spermatogonia to produce spermatocytes; two meiotic divisions of spermatocytes to generate haploid round spermatids; and spermiogenesis, the final phase that involves the maturation of early-round spermatids into elongated mature spermatids. A number of miRNAs are expressed abundantly in male germ cells throughout spermatogenesis, while piRNAs are only present in pachytene spermatocytes and round spermatids. In this review, we first address the synthesis, mechanisms of action, and functions of siRNA, miRNA, and piRNA, and then we focus on the recent advancements in defining the small RNAs in the regulation of spermatogenesis. Concerns pertaining to the use of siRNAs in exploring spermatogenesis mechanisms and open questions in miRNAs and piRNAs in this field are highlighted. The potential applications of small RNAs to male contraception and treatment for male infertility and testicular cancer are also discussed. Show less

Recent reports have demonstrated that adult tissue cells can be induced to pluripotency, the iPS cells, mostly with the addition of genes delivered using viruses. Also, several publications both in mouse and in human have demonstrated that spermatogonial stem cells (SSCs) from testes can convert back to embryonic stem (ES)-like cells without the addition of genes. Furthermore, these pluripotent ES-like cells can differentiate into all three germ layers and organ lineages. Thus, SSCs have great potential for cell-based, autologous organ regeneration therapy for various diseases. We obtained testes from organ donors and using 1 g pieces of tissue (biopsy size) we demonstrate that testis germ cells (putative SSCs and/or their progenitors) reprogram to pluripotency when removed from their stem cell niche and when appropriate growth factors and reagents in embryonic stem cell medium are added. In addition, our method of obtaining pluripotent ES-like cells from germ cells is simpler than the described methods and may be more suitable if this procedure is developed for the clinic to obtain pluripotent cells to cure disease. Show less

Recent reports have demonstrated that adult cells can be reprogrammed to pluripotency, but mostly with genes delivered using retroviruses. Some of the genes are cancer causing; thus, these adult-derived embryonic stem (ES)-like cells cannot be used for therapy to cure human diseases. Remarkably, it has also been demonstrated recently by several groups that, in mice, spermatogonial stem cells (SSCs) can be reprogrammed to ES-like cells without the necessity of exogenously added genes. SSCs constitute one of the most important stem cell systems in the body, not only because they produce spermatozoa that transmit genetic information from generation to generation, but also because of the recent studies showing their remarkable plasticity. Very little is known about SSCs in humans, except for the earlier work of Clermont and colleagues who demonstrated that there are A(dark) and A(pale) spermatogonia, with the A(dark) referred to as the reserve stem cells and the A(pale) being the renewing stem cells. We now demonstrate that G protein-coupled receptor 125 (GPR125) may be a marker for human SSCs. Putative human SSCs can also be reprogrammed to pluripotency. We were able to achieve this result without the addition of genes, suggesting that human SSCs have considerable potential for cell-based, autologous organ regeneration therapy for various diseases. Show less