Biology subjects

MacLean, J. A.

Publications and source records attributed to MacLean, J. A..

6 recordsLinked to original sources

bioRxiv2025

Transgenerational effects of perinatal cannabis exposure on female reproductive parameters in mice

The use of cannabis during pregnancy and nursing is a growing public health concern, and the multigenerational impacts of perinatal cannabis exposure remain largely unknown. To address this knowledge gap, we sought to examine the long-term consequences of perinatal cannabis use on reproductive function and how it might impact subsequent generations. Pregnant female mice were exposed to control vehicle or cannabis extract [25, 100, or 200 mg/ml {Delta}9-tetrahydrocannabinol (THC) in the cannabis extract] from gestational day 1 to postnatal day 21 (twice/day), encompassing the duration of pregnancy through weaning. Based on plasma THC concentrations in F0 females, we chose 100 and 200 mg/ml THC in the cannabis extract for subsequent studies. The selected doses and exposure conditions did not disrupt pregnancy or nursing in F0 females. Pregnancy and neonatal outcomes, including gestational length, litter size, and sexual ratio, were not affected by cannabis exposure. However, cannabis-exposed neonatal F1 pups were smaller. Cannabis exposure delayed vaginal opening as a sign of puberty onset and disrupted estrous cyclicity in F1 females. However, its effects were minor in F2 and F3 females. F1-F3 females showed no abnormal ovarian and uterine histology or plasma estradiol-17{beta} levels and could produce normal offspring without pregnancy issues. These results suggest that the hypothalamus and pituitary are likely perturbed by perinatal cannabis exposure, and the early hypothalamus-pituitary-ovarian axis is disrupted in F1 females. However, they are not sufficient to compromise adult reproductive function. The present results indicate limited transgenerational effects of perinatal cannabis exposure on female reproductive parameters.

pharmacology and toxicology↗

bioRxiv2025

Multiple lesion inductions intensify central sensitization driven by neuroinflammation in a mouse model of endometriosis.

IntroductionEndometriosis is an inflammatory disease associated with chronic pelvic pain (CPP). Growing evidence indicates that endometriotic lesions are not the sole source of pain. Instead, central nervous system (CNS) dysfunction created by prolonged peripheral and central sensitization plays a role in developing endometriosis-associated CPP. This study investigated how CPP is established using a multiple lesion induction mouse model of endometriosis, as repeated retrograde menstruation is considered underlying endometriosis pathogenesis. MethodsWe generated endometriosis-like lesions by injecting endometrial tissue fragments into the peritoneal cavity in mice. The mice received a single (1x) or multiple inductions (6x) to simulate recurrent retrograde menstruation. Lesion development, hyperalgesia by behavioral testing, signs of peripheral sensitization, chronic inflammation, and neuroinflammation were examined with lesions, peritoneal fluids, dorsal root ganglia (DRG), spinal codes, and brain. ResultsMultiple lesion inductions increased lesion numbers and elevated abdominal and hind paw hypersensitivity compared to single induction mice. Elevated persistent glial cell activation across several brain regions and/or spinal cords was found in the multiple induction mice. Specifically, IBA1+ microglial soma size was increased in the hippocampus and thalamus. IBA1+ cells were abundant in the cortex, hippocampus, thalamus, and hypothalamus of the multiple induction mice. GFAP+ astrocytes were mainly elevated in the hippocampus. Elevated TRPV1, SP, and CGRP expressions in the DRG were persistent in the multiple induction mice. Furthermore, multiple inductions induced the severe disappearance of TIM4hi MHCIIlo residential macrophages and the influx of increased proinflammatory TIM4lo MHCIIhi macrophages in the peritoneal cavity. The single and multiple inductions elevated secreted TNF, IL-1{beta}, and IL-6 levels in the peritoneal cavity at 2 weeks. Elevated cytokine levels returned to the pre-induction levels in the single induction mice at 6 weeks; however, they remained elevated in the multiple induction mice. ConclusionsOur results indicate that the repeatedly occurring lesion inductions (=mimic retrograde menstruation) can be a peripheral stimulus that induces nociceptive pain and creates composite chronic inflammatory stimuli to cause neuroinflammation and sensitize the CNS. The circuits of neuroplasticity and stimulation of peripheral organs via a feedback loop of neuroinflammation may mediate widespread endometriosis-associated CPP.

molecular biology↗

bioRxiv2024

Environmentally-relevant doses of bisphenol A and S exposure in utero disrupt germ cell programming across generations resolved by single nucleus multi-omics

BackgroundExposure to endocrine-disrupting chemicals (EDCs), such as bisphenol A (BPA), disrupts reproduction across generations. Germ cell epigenetic alterations are proposed to bridge transgenerational reproductive defects resulting from EDCs. Previously, we have shown that prenatal exposure to environmentally relevant doses of BPA or its substitute, BPS, caused transgenerationally maintained reproductive impairments associated with neonatal spermatogonial epigenetic changes in male mice. While epigenetic alterations in germ cells can lead to transgenerational phenotypic variations, the mechanisms sustaining these changes across generations remain unclear. ObjectivesThis study aimed to systematically elucidate the mechanism of transgenerational inherence by prenatal BPA and BPS exposure in the murine germline from F1 to F3 generations at both transcriptomic and epigenetic levels. MethodsBPA or BPS with doses of 0 (vehicle control), 0.5, 50, or 1000 {micro}g/kg/b.w./day was orally administered to pregnant CD-1 females (F0) from gestational day 7 to birth. Sperm counts and motility were examined in F1, F2, and F3 adult males. THY1+ germ cells on postnatal day 6 from F1, F2, and F3 males at a dose of 50 {micro}g/kg/b.w./day were used for analysis by single-nucleus (sn) multi-omics (paired snRNA-seq and snATAC-seq on the same nucleus). ResultsPrenatal exposure to BPA and BPS with 0.5, 50, and 1000 {micro}g/kg/b.w./day reduced sperm counts in mice across F1 to F3 generations. In the F1 neonatal germ cells, ancestral BPA or BPS exposure with 50 {micro}g/kg/b.w./day resulted in increased differentially expressed genes (DEGs) associated with spermatogonial differentiation. It also disrupted the balance between maintaining the undifferentiated and differentiating spermatogonial populations. Differentially accessible peaks (DAPs) by snATAC-seq were primarily located in the promoter regions, with elevated activity of key transcription factors, including SP1, SP4, and DMRT1. Throughout F1-F3 generations, biological processes related to mitosis/meiosis and metabolic pathways were substantially up-regulated in BPA-or BPS-exposed groups. While the quantities of DEGs and DAPs were similar in F1 and F2 spermatogonia, with both showing a significant reduction in F3. Notably, approximately 80% of DAPs in F1 and F2 spermatogonia overlapped with histone post-translational modifications linked to transcription activation, such as H3K4me1/2/3 and H3K27ac. Although BPA exerted more potent effects on gene expression in F1 spermatogonia, BPS induced longer-lasting effects on spermatogonial differentiation across F1 to F3 males. Interestingly, DMRT1 motif activity was persistently elevated across all three generations following ancestral BPA or BPS exposure. DiscussionOur work provides the first systematic analyses for understanding the transgenerational dynamics of gene expression and chromatin landscape following prenatal exposure to BPA or BPS in neonatal spermatogonia. These results suggest that prenatal exposure to environmentally relevant doses of BPA or BPS alters chromatin accessibility and transcription factor motif activities, consequently contributing to disrupted transcriptional levels in neonatal germ cells, and some are sustained to F3 generations, ultimately leading to the reduction of sperm counts in adults.

pharmacology and toxicology↗

bioRxiv2023

High-fat diets promote peritoneal inflammation and augment endometriosis-associated abdominal hyperalgesia

Immune dysfunction is one of the central components in the development and progression of endometriosis by establishing a chronic inflammatory environment. Western-style high-fat diets (HFD) have been linked to greater systemic inflammation to cause metabolic and chronic inflammatory diseases, and are also considered an environmental risk factor for gynecologic diseases. Here, we aimed to examine how HFD alter an inflammatory environment in endometriosis and discern their contribution to endometriotic-associated hyperalgesia. Our results showed that HFD-induced obesity enhanced abdominal mechanical allodynia that was induced by endometriotic lesions. Peritoneal inflammatory macrophages and cytokine levels increased by lesion induction were elevated by chronic exposure to HFD. Pain-related mediators in the dorsal root ganglia were further stimulated after lesion induction under the HFD condition. Although HFD did not affect inflammatory macrophages in the peritoneal cavity without lesion induction, the diversity and composition of the gut microbiota were clearly altered by HFD as a sign of low-grade systemic inflammation. Thus, HFD alone might not establish a local inflammatory environment in the pelvic cavity, but it can contribute to further enhancing chronic inflammation, leading to the exacerbation of endometriosis-associated abdominal hyperalgesia following the establishment and progression of the disease.

physiology↗

bioRxiv2022

Niclosamide targets macrophages to rescue the disrupted peritoneal homeostasis in endometriosis

Due to the vital roles of macrophages in the pathogenesis of endometriosis, targeting macrophages could be a new therapeutic direction. Here, we investigated the efficacy of niclosamide for the resolution of perturbed microenvironment caused by dysregulated macrophages in a mouse model of endometriosis. Single-cell transcriptomic analysis revealed the heterogeneity of macrophage subpopulations including three newly identified intermediate subtypes with sharing characteristics of traditional "small" or "large" peritoneal macrophages (SPMs and LPMs) in the peritoneal cavity. Endometriosis-like lesions (ELL) enhanced the differentiation of recruited macrophages, promoted the replenishment of resident LPMs, and increased ablation of embryo-derived LPMs, which were stepwise suppressed by niclosamide. In addition, niclosamide reversed intercellular communications between macrophages and B cells which were disrupted by ELL. Therefore, niclosamide rescued the perturbed microenvironment in endometriosis through its fine regulations on the dynamic progression of macrophages and could be a new promising therapy for endometriosis. SummaryNiclosamide tunes the dynamic progression of peritoneal macrophages and their intercellular communications with B cells to rescue the disrupted microenvironment in the peritoneal cavity in a mouse model of endometriosis. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=155 SRC="FIGDIR/small/487220v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@e6700eorg.highwire.dtl.DTLVardef@c6c557org.highwire.dtl.DTLVardef@1c60b92org.highwire.dtl.DTLVardef@121bce6_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphic AbstractC_FLOATNO C_FIG

molecular biology↗

bioRxiv2021

Vapor cannabis exposure generationally affects male reproductive functions in mice

This study was performed to examine whether vapor exposure to cannabis plant matter negatively impacts male reproductive functions and testis development in mice. Adult CD-1 male mice (F0) were exposed to air (control) or 200 mg of vaporized cannabis plant matter 3x/day over a 10 day period. Subsequently, F0 males were bred with drug naive CD-1 females to generate F1 males, and F1 offspring were used to generate F2 males. Cannabis vapor exposure decreased sperm count and/or motility in F0 and F1 males and disrupted the progression of germ cell development, as morphometric analyses exhibited an abnormal distribution of the stages of spermatogenesis in F0 males. Although plasma levels of testosterone were not affected by cannabis exposure in any ages or generations of males, dysregulated steroidogenic enzymes, Cyp11a1 and Cyp19a1, were observed in F0 testis. In the neonatal testis from F1 males, while apoptosis was not altered, DNA damage and DNMT1, but not DNMT3A and DNMT3B, were increased in germ cells following cannabis exposure. In contrast, the alterations of DNA damage and DNMT1 expression were not observed in F2 neonatal males. These results suggest that cannabis vapor exposure generationally affects male reproductive functions, probably due to disruption of spermatogenesis in the developing testis. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=156 SRC="FIGDIR/small/457271v1_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@1a6782borg.highwire.dtl.DTLVardef@1b5e42org.highwire.dtl.DTLVardef@c94d78org.highwire.dtl.DTLVardef@1fd269d_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSO_LICannabis vapor exposure to adult males impairs sperm counts, motility and spermatogenesis. C_LIO_LICannabis vapor exposure to F0 males causes reduced sperm counts in F1, but not in F2 males. C_LIO_LIPlasma testosterone levels are not affected in F0, F1 and F2 males by cannabis exposure. C_LIO_LICannabis increases DNA damage and the expression of DNA methyltransferase (DNMT) 1 in the F1 neonatal testis. C_LI

pharmacology and toxicology↗