The effects of environmental enrichment on nicotine sensitization in a rodent model of schizophrenia

Environmental enrichment, for more than fifty years, has shown to increase learning in behaviors and to alter some brain structures (Renner and Rosenzweig). Some brain changes that occur when environmental enrichment is implemented include the following: increases in cortical thickness, especially the occipital cortex, increases in size of neuronal cell bodies, number of dendrites and dendritic spines, increases in astrocyte branching, increases in the number of brain blood capillaries, and increases in mitochondria (an indication of higher metabolic activity) (Stairs and Bard). It has been shown in research studies that rats in the environmental enrichment group are less sensitive to nicotine effects, both repeated and acute, than rats in isolated situations (Green et al). This is so because enrichment changes the intensity of the acute administration of drugs of abuse. Rats are stimulated by the environment, rather than a particular stimulant

A Comparison between Schizophrenia and Autism

Autism spectrum disorder and schizophrenia share a substantial number of etiologic and phenotypic characteristics. Still, no direct comparison of both disorders has been performed to identify differences and commonalities in brain structure. In this voxel based morphometry study, 34 patients with autism spectrum disorder, 21 patients with schizophrenia and 26 typically developed control subjects were included to identify global and regional brain volume alterations. No global gray matter or white matter differences were found between groups. In regional data, patients with autism spectrum disorder compared to typically developed control subjects showed smaller gray matter volume in the amygdala, insula, and anterior medial prefrontal cortex. Compared to patients with schizophrenia, patients with autism spectrum disorder displayed smaller gray matter volume in the left insula. Disorder specific positive correlations were found between mentalizing ability and left amygdala volume in autism spectrum disorder, and hallucinatory behavior and insula volume in schizophrenia. Results suggest the involvement of social brain areas in both disorders. Further studies are needed to replicate these findings and to quantify the amount of distinct and overlapping neural correlates in autism spectrum disorder and schizophrenia

Diaphragmatic Injuries among Severely Injured Patients (ISS ≥ 16)—An Indicator of Injury Pattern and Severity of Abdominal Trauma

Background and Objectives: Abdominal trauma among severely injured patients with an injury severity score (ISS) of 16 and above can lead to potentially life-threatening injuries that might need immediate surgical intervention. Traumatic injuries to the diaphragm (TID) are a challenging condition often accompanied by other injuries in the thoracoabdominal region. Materials and Methods: We retrospectively analyzed the occurrence and clinical course of TID among severely injured patients treated at our center between 2008 and 2019 and compared them to other groups of severely injured patients without TID. Results: Thirty-five patients with TID and a median ISS of 41 were treated in the period mentioned above. They were predominantly middle-aged men and mostly victims of blunt trauma as a consequence of motor vehicle accidents. A total of 70.6% had left-sided TID, and in 69.6%, the size of defect was larger than 10 cm. The diagnosis was made with computed tomography (CT) in 68.6% of the cases, while in 25.8%, it was made intraoperatively or delayed by a false-negative initial CT scan, and in 5.7%, an intraoperative diagnosis was made without preoperative CT imaging. Surgical repair was mostly conducted via laparotomy, performing a direct closure with continuous suture. A comparison to 191 patients that required laparotomy for abdominal injuries other than TID revealed significantly higher rates of concomitant injuries to several abdominal organs among patients suffering from TID. Compared to all other severely injured patients treated in the same period (n = 1377), patients suffering from TID had a significantly higher median ISS and a longer mean duration of hospital stay. Conclusions: Our findings show that TID can be seen as an indicator of particularly severe thoracoabdominal trauma that requires increased attention from the treatment team so as not to miss relevant concomitant injuries that require immediate intervention

TIGIT+ iTregs elicited by human regulatory macrophages control T cell immunity

Human regulatory macrophages (Mreg) have shown early clinical promise as a cell-based adjunct immunosuppressive therapy in solid organ transplantation. It is hypothesised that recipient CD4(+) T cell responses are actively regulated through direct allorecognition of donor-derived Mregs. Here we show that human Mregs convert allogeneic CD4(+) T cells to IL-10-producing, TIGIT(+) FoxP3(+)-induced regulatory T cells that non-specifically suppress bystander T cells and inhibit dendritic cell maturation. Differentiation of Mreg-induced Tregs relies on multiple non-redundant mechanisms that are not exclusive to interaction of Mregs and T cells, including signals mediated by indoleamine 2,3-dioxygenase, TGF-beta, retinoic acid, Notch and progestagen-associated endometrial protein. Preoperative administration of donor-derived Mregs to living-donor kidney transplant recipients results in an acute increase in circulating TIGIT(+) Tregs. These results suggest a feed-forward mechanism by which Mreg treatment promotes allograft acceptance through rapid induction of direct-pathway Tregs

The Effects of Environmental Enrichment on Adolescent Nicotine Sensitization in a Rodent Model of Schizophrenia

Our lab has shown that neonatal treatment with quinpirole, a dopamine D2/D3 agonist, to rats resulted in an increase in dopamine D2‐like receptor sensitivity that persists throughout the animal’s lifetime without a change in receptor number, consistent with schizophrenia. Approximately 80‐85% of schizophrenics smoke cigarettes, and there is no delineated mechanism for this observation. Our lab has also shown more robust sensitization and accumbal dopamine release in response to nicotine in adolescent rats neontally treated with quinpirole compared to controls. This study analyzed whether environmental enrichment, known to reduce sensitization to psychostimulants, may also reduce or block enhanced sensitization to nicotine in this model. Male and female rats were treated with either quinpirole (1 mg/kg) or saline from postnatal day (P)1‐21. After weaning at P21, animals were raised in either environmentally enriched or isolated housing throughout the experiment. Beginning on P33, animals were ip administered either nicotine (0.5 mg/kg free base) or saline 10 min before placement in a square locomotor arena and behavioral activity measured every second day from P33‐49. Results revealed that animals given neonatal quinpirole treatment and reared in an enriched environment demonstrated more robust sensitization to nicotine than all other groups. Animals given neonatal quinpirole or saline treatment followed by nicotine in adolescence and raised in isolated housing conditions were equivalent, but demonstrated more robust sensitization compared to enriched rats Page 13 of 35 neonatally treated with saline and administered nicotine in adolescence. Results here show that environmental enrichment enhanced nicotine sensitization in rats neonatally treated with quinpirole, which is in contrast to the blockade of sensitization to nicotine which has previously been shown in normal animals. Importantly, these results show that increases in D2 receptor sensitivity interacts with environmental enrichment differently than in normal animals and the manner in which the animal responds to nicotine, which may have implications towards smoking cessation in schizophrenia

The Effects of Environmental Enrichment on Adolescent Nicotine Sensitization in a Rodent Model of Schizophrenia

Our lab has shown that neonatal treatment with quinpirole, a dopamine D2/D3 agonist, to rats resulted in an increase in dopamine D2-like receptor sensitivity that persists throughout the animal’s lifetime without a change in receptor number, consistent with schizophrenia. Approximately 80-85% of schizophrenics smoke cigarettes, and there is no delineated mechanism for this observation. Our lab has also shown more robust sensitization and accumbal dopamine release in response to nicotine in adolescent rats neontally treated with quinpirole compared to controls. This study analyzed whether environmental enrichment, known to reduce sensitization to psychostimulants, may also reduce or block enhanced sensitization to nicotine in this model. Male and female rats were treated with either quinpirole (1 mg/kg) or saline from postnatal day (P)1-21. After weaning at P21, animals were raised in either environmentally enriched or isolated housing throughout the experiment. Beginning on P33, animals were ip administered either nicotine (0.5 mg/kg free base) or saline 10 min before placement in a square locomotor arena and behavioral activity measured every second day from P33-49. Results revealed that animals given neonatal quinpirole treatment and reared in an enriched environment demonstrated more robust sensitization to nicotine than all other groups. Animals given neonatal quinpirole or saline treatment followed by nicotine in adolescence and raised in isolated housing conditions were equivalent, but demonstrated more robust sensitization compared to enriched rats neonatally treated with saline and administered nicotine in adolescence. Results here show that environmental enrichment enhanced nicotine sensitization in rats neonatally treated with quinpirole, which is in contrast to the blockade of sensitization to nicotine which has previously been shown in normal animals. Importantly, these results show that increases in D2 receptor sensitivity interacts with environmental enrichment differently than in normal animals and the manner in which the animal responds to nicotine, which may have implications towards smoking cessation in schizophrenia

Preeclampsia: multiple approaches for a multifactorial disease

Preeclampsia is a pregnancy-specific disorder characterized by hypertension and excess protein excretion in the urine. It is an important cause of maternal and fetal morbidity and mortality worldwide. The disease is almost exclusive to humans and delivery of the pregnancy continues to be the only effective treatment. The disorder is probably multifactorial, although most cases of preeclampsia are characterized by abnormal maternal uterine vascular remodeling by fetally derived placental trophoblast cells. Numerous in vitro and animal models have been used to study aspects of preeclampsia, the most common being models of placental oxygen dysregulation, abnormal trophoblast invasion, inappropriate maternal vascular damage and anomalous maternal-fetal immune interactions. Investigations into the pathophysiology and treatment of preeclampsia continue to move the field forward, albeit at a frustratingly slow pace. There remains a pressing need for novel approaches, new disease models and innovative investigators to effectively tackle this complex and devastating disorder

Data from: Structural alterations of the social brain: a comparison between schizophrenia and autism

Autism spectrum disorder and schizophrenia share a substantial number of etiologic and phenotypic characteristics. Still, no direct comparison of both disorders has been performed to identify differences and commonalities in brain structure. In this voxel based morphometry study, 34 patients with autism spectrum disorder, 21 patients with schizophrenia and 26 typically developed control subjects were included to identify global and regional brain volume alterations. No global gray matter or white matter differences were found between groups. In regional data, patients with autism spectrum disorder compared to typically developed control subjects showed smaller gray matter volume in the amygdala, insula, and anterior medial prefrontal cortex. Compared to patients with schizophrenia, patients with autism spectrum disorder displayed smaller gray matter volume in the left insula. Disorder specific positive correlations were found between mentalizing ability and left amygdala volume in autism spectrum disorder, and hallucinatory behavior and insula volume in schizophrenia. Results suggest the involvement of social brain areas in both disorders. Further studies are needed to replicate these findings and to quantify the amount of distinct and overlapping neural correlates in autism spectrum disorder and schizophrenia

Immune-mediated hepatitis drives low-level fusion between hepatocytes and adult bone marrow cells

Background/Aims: The role of adult bone marrow-derived cells (BMC) in hepatic regeneration is controversial. Both transdifferentiation of BMC as well as fusion with hepatocytes have been suggested in toxin-based and genetic selection models. Methods: We have developed a transgenic mouse model of immune-mediated hepatitis to clarify the role of BMC in liver regeneration following injury mediated by T cells. Results: Repeated adoptive transfer of transgenic T cells into bone marrow chimeras resulted in multiple waves of hepatitis. Hepatocytes derived from donor bone marrow were identified using a self-protein that does not interfere with hepatocyte function and proliferation in recipient animals. Some cells contained one recipient nucleus and another independent donor bone marrow-derived nucleus, suggesting that cellular fusion plays some role in liver repair after immune hepatitis. However, despite pronounced infiltration by myeloid cells, the frequency of fusion was extremely low. Conclusions: This study provides a unique, clinically relevant model in which fusion hepatocytes can be purified and characterized by the expression of donor MHC antigen. It demonstrates that although fusion between BMC and hepatocytes occurs under conditions of inflammation that correspond to human disease, its frequency needs to be increased to be of any therapeutic value