Delta-Like Homolog 2 Facilitates Malignancy of Hepatocellular Carcinoma via Activating EGFR/PKM2 Signaling Pathway.

Delta-like homolog 2 (DLK2) plays a crucial role in adipogenesis, chondrogenic differentiation, and the progression of certain cancers. However, the key roles of DLK2 underlying the progression of hepatocellular carcinoma (HCC) remain ambiguous. In the current study, we demonstrate that DLK2 is upregulated in HCC, significantly correlated with clinicopathological variables and serves as an independent diagnostic marker. Functional assays reveal that DLK2 facilitates malignant progression of HCC in vitro and in vivo models. Mechanistically, DLK2 binds to EGFR resulting in its auto-phosphorylation, which activates NK-κB pathway leading to P65-dependent transcriptional upregulation of PKM2. Furthermore, that elevates both enzyme-dependent and -independent activities of PKM2 contributing to cancer proliferation and metastasis. In summary, our findings demonstrate a novel pro-tumoral role and mechanism of DLK2 in the regulation of HCC malignant progression, suggesting its potential as a clinical diagnostic marker and therapeutic target.

Histone demethylase PHF8 promotes prostate cancer metastasis via the E2F1-SNAI1 axis.

Metastasis is the primary culprit behind cancer-related fatalities in multiple cancer types, including prostate cancer. Despite great advances, the precise mechanisms underlying prostate cancer metastasis are far from complete. By using a transgenic mouse prostate cancer model (TRAMP) with and without Phf8 knockout, we have identified a crucial role of PHF8 in prostate cancer metastasis. By complexing with E2F1, PHF8 transcriptionally upregulates SNAI1 in a demethylation-dependent manner. The upregulated SNAI1 subsequently enhances epithelial-to-mesenchymal transition (EMT) and metastasis. Given the role of the abnormally activated PHF8/E2F1-SNAI1 axis in prostate cancer metastasis and poor prognosis, the levels of PHF8 or the activity of this axis could serve as biomarkers for prostate cancer metastasis. Moreover, targeting this axis could become a potential therapeutic strategy for prostate cancer treatment. © 2024 The Pathological Society of Great Britain and Ireland.

Evaluating the clinical efficacy and safety of concurrent chemoradiotherapy with cisplatin and nab-paclitaxel in postoperative early-stage cervical cancer.

OBJECTIVE: A preclinical study showed that nab-paclitaxel acted as a radiosensitizer and improved tumor radiotherapy in a supra-additive manner. In this study, we aimed to evaluate the clinical efficacy and safety of concurrent chemoradiotherapy (CCRT) with cisplatin and nab-paclitaxel in postoperative early-stage cervical cancer with an unfavorable prognosis. METHODS: Eligible patients with stage IB1-IIA2 (FIGO 2009) cervical carcinoma were recruited retrospectively between August 2018 to May 2021. Patients in both the cisplatin and nab-paclitaxel groups received postoperative radiotherapy and weekly intravenous cisplatin 40 mg/m2 or nab-paclitaxel 100 mg concurrently. An analysis of overall survival, progression-free survival, and adverse reactions was conducted. RESULTS: A total of 105 early-stage cervical cancer patients were included into our study. The median follow-up time was 38.7 months. The 3-year overall survival and progression-free survival in both group was similar. The cycles of chemotherapy in the cisplatin group were less than those in the nab-paclitaxel group (4.5 vs. 5.0; p = 0.001). Patients in the cisplatin group had a significantly higher frequency of hematological adverse events than patients in the nab-paclitaxel group (P < 0.05). Patients in the cisplatin group had a significantly higher frequency of grade 3-4 leukopenia (46.1% vs. 18.9%; P = 0.03), grade 1-2 thrombocytopenia (32.7% vs. 9.5%; P = 0.014) than patients in the nab-paclitaxel group. Gastrointestinal reactions, such as vomiting, nausea, and anorexia were significantly reduced in the nab-paclitaxel group compared with those in the cisplatin group. Regarding the effects on alopecia, the incidence rate of the nab-paclitaxel group was higher than that of the cisplatin group (P = 0.001). There were no differences between the groups in terms of other adverse reactions. CONCLUSION: The results of this study indicate that nab-paclitaxel-based concurrent radiotherapy is tolerable and effective, and can be considered an alternative to cisplatin chemotherapy.

The Association of Homocysteine and Diabetic Retinopathy in Homocysteine Cycle in Chinese Patients With Type 2 Diabetes.

Objective: This study aimed to explore the relationship between homocysteine (Hcy) and diabetic retinopathy (DR) and the impacts of the Hcy pathway on this relationship against this background. Methods: This study retrieved 1979 patients with type 2 diabetes (T2D) from the First Affiliated Hospital of Liaoning Medical University in Jinzhou, Liaoning Province, China. Multiple logistic regression was used to analyze the effects of Hcy cycle on the relationship between Hcy and DR. Spearman's rank correlation analysis was used to analyze the correlation between risk factors related to DR progression and Hcy. Finally, the results of logistic regression were supplemented by mediation analysis. Results: We found there was a negative correlation between low concentration of Hcy and DR (OR : 0.83, 95%CI: 0.69-1). After stratifying all patients by cysteine (Cys) or Methionine (Met), this relationship remained significant only in low concentration of Cys (OR: 0.75, 95%CI: 0.61-0.94). Through the RCS curve, we found that the effect of Hcy on DR presents a U-shaped curve relationship. Mediating effect in Met and Hcy cycles was also significant [Total effect c (OR: 0.968, 95%CI: 0.938-0.998), Direct effect path c' (OR: 0.969, 95%CI: 0.940-0.999), Path a (OR: 1.047, 95%CI: 1.004-1.091), Path b (OR: 0.964, 95%CI: 0.932-0.998)]. Conclusions: The relationship between Hcy and DR presents a U-shaped curve and the homocysteine cycle pathway has an impact on it. And too low concentration of Hcy indicates a lack of other substances, such as vitamins. It is suggested that the progression of DR is the result of a combination of many risk factors. Further prospective studies are needed to determine the role of Hcy in the pathogenesis of DR.

Role of chronic neuroinflammation in neuroplasticity and cognitive function: A hypothesis.

OBJECTIVE: Evaluating the efficacy of 3,6'-dithioPomalidomide in 5xFAD Alzheimer's disease (AD) mice to test the hypothesis that neuroinflammation is directly involved in the development of synaptic/neuronal loss and cognitive decline. BACKGROUND: Amyloid-ß (Aß) or tau-focused clinical trials have proved unsuccessful in mitigating AD-associated cognitive impairment. Identification of new drug targets is needed. Neuroinflammation is a therapeutic target in neurodegenerative disorders, and TNF-α a pivotal neuroinflammatory driver. NEW HYPOTHESIS: AD-associated chronic neuroinflammation directly drives progressive synaptic/neuronal loss and cognitive decline. Pharmacologically mitigating microglial/astrocyte activation without altering Aß generation will define the role of neuroinflammation in AD progression. MAJOR CHALLENGES: Difficulty of TNF-α-lowering compounds reaching brain, and identification of a therapeutic-time window to preserve the beneficial role of neuroinflammatory processes. LINKAGE TO OTHER MAJOR THEORIES: Microglia/astroglia are heavily implicated in maintenance of synaptic plasticity/function in healthy brain and are disrupted by Aß. Mitigation of chronic gliosis can restore synaptic homeostasis/cognitive function.

Extended field or pelvic intensity-modulated radiotherapy with concurrent cisplatin chemotherapy for the treatment of post-surgery multiple pelvic lymph node metastases in cervical cancer patients: a randomized, multi-center phase II clinical trial.

BACKGROUND: To prospectively compare the outcomes and side effects between groups of postoperative cervical cancer patients with multiple pelvic lymph node metastases who were treated with extended field or pelvic intensity-modulated radiotherapy (IMRT) with concurrent cisplatin chemotherapy. METHODS: Cervical carcinoma patients with International Federation of Gynecology and Obstetrics (FIGO) stage Ib-IIa, who underwent radical hysterectomy and had histologically confirmed multiple (≥2) pelvic lymph node metastases, were enrolled into this study. The patients were randomly assigned to pelvic-IMRT or extended field-IMRT (45 Gy/25 Fx) group. Patients in either group received concurrent cisplatin chemotherapy (40 mg/m2) starting on the first day of irradiation. RESULTS: Until December 31th 2017, 129 patients were initially enrolled into this study. During the study, 3 patients were dropped out due to either incompletion of the study or exclusion by the criteria. Consequently, 64 patients completed pelvic-IMRT, and 62 patients completed extended field-IMRT. Median follow-up period was 61.30 months in the extended field-IMRT group and 60.60 months in the pelvic-IMRT group. Five-year actuarial survival probability was 0.759 (95% CI: 0.619-0.854) in the extended field-IMRT group which was not significantly different from that of the pelvic-IMRT group [0.824 (95% CI: 0.690-0.905), P=0.442]. Similarly, the five-year progression-free probability was 0.720 (95% CI: 0.576-0.822) in the extended field-IMRT group, which was not significantly different from that of the pelvic-IMRT group [0.781 (95% CI: 0.637-0.874), P=0.389]. In addition, there was no significant difference between the two groups in hematology and gastrointestinal tract toxicities. CONCLUSIONS: Post-operative pelvic-IMRT or extended field-IMRT with concurrent cisplatin chemotherapy had similar outcomes in terms of survival rates and adverse events in cervical carcinoma patients at FIGO stage Ib-IIa with multiple pelvic lymph nodes metastases.

Antiangiogenic Activity and in Silico Cereblon Binding Analysis of Novel Thalidomide Analogs.

Due to its antiangiogenic and anti-immunomodulatory activity, thalidomide continues to be of clinical interest despite its teratogenic actions, and efforts to synthesize safer, clinically active thalidomide analogs are continually underway. In this study, a cohort of 27 chemically diverse thalidomide analogs was evaluated for antiangiogenic activity in an ex vivo rat aorta ring assay. The protein cereblon has been identified as the target for thalidomide, and in silico pharmacophore analysis and molecular docking with a crystal structure of human cereblon were used to investigate the cereblon binding abilities of the thalidomide analogs. The results suggest that not all antiangiogenic thalidomide analogs can bind cereblon, and multiple targets and mechanisms of action may be involved.

3,6'-dithiopomalidomide reduces neural loss, inflammation, behavioral deficits in brain injury and microglial activation.

Traumatic brain injury (TBI) causes mortality and disability worldwide. It can initiate acute cell death followed by secondary injury induced by microglial activation, oxidative stress, inflammation and autophagy in brain tissue, resulting in cognitive and behavioral deficits. We evaluated a new pomalidomide (Pom) analog, 3,6'-dithioPom (DP), and Pom as immunomodulatory agents to mitigate TBI-induced cell death, neuroinflammation, astrogliosis and behavioral impairments in rats challenged with controlled cortical impact TBI. Both agents significantly reduced the injury contusion volume and degenerating neuron number evaluated histochemically and by MRI at 24 hr and 7 days, with a therapeutic window of 5 hr post-injury. TBI-induced upregulated markers of microglial activation, astrogliosis and the expression of pro-inflammatory cytokines, iNOS, COX-2, and autophagy-associated proteins were suppressed, leading to an amelioration of behavioral deficits with DP providing greater efficacy. Complementary animal and cellular studies demonstrated DP and Pom mediated reductions in markers of neuroinflammation and α-synuclein-induced toxicity.

Identification of a six lncRNAs signature as novel diagnostic biomarkers for cervical cancer.

Cervical cancer is a tumor with the second highest morbidity and mortality in the world, and it is also the most common cancer and the eighth lethal factor among malignant tumors in Chinese female. This study aimed to identify long noncoding RNAs (lncRNAs) that related to diagnosis and prognosis in cervical cancer to improve early diagnosis and treatment. First, we extracted transcriptome profilings of cervical cancer samples from the cancer genome atlas (TCGA) database, and then extracted the lncRNAs and mRNAs expression profiles. Based on the lncRNAs expression profiles of test set, we screened lncRNAs that related to progression of cervical cancer tumors. We found six lncRNAs associated with tumor progression in cervical cancer patients, in which five lncRNAs have highly similar expression patterns but the other one has the opposite expression pattern. We found that these six lncRNAs might be related to keratinization and immunity by enrichment analysis, and two of them (AC126474 and C5orf66-AS1) were associated with prognosis in patients with cervical cancer. And these results were validated using the validation set. Overall, we identified six lncRNAs that played an important role in the development of cervical cancer, and two of them might be associated with the prognosis of cervical cancer, which provides new insight into the diagnosis and treatment of cervical cancer.

Identification of four differentially methylated genes as prognostic signatures for stage I lung adenocarcinoma.

BACKGROUND: Lung adenocarcinoma (LUAD) is the main subtype of non-small cell lung cancer with a low survival prognosis. We aimed to generate a prognostic model for the postoperative recurrence of LUAD. METHODS: The methylated DNA data of LUAD patients were downloaded from the Cancer Genome Atlas (TCGA). The differentially methylated genes were identified and protein-protein interacting network was constructed, with which prognostic signature of this cancer was generated. Survival and functional pathways analysis w used to evaluate the clustering ability of the prognostic signature. RESULTS: We identified 151 differentially methylated genes related to relapse-free survival of patients with LUAD. Nine hub genes were identified in PPI network, with which 4 gene pair signature was selected as prognostic signature. The potential functions of 6 genes (JDP2, SERPINA5, PLG, SEMG2, RFX5, and POLR3B) in the 4-gene pair signature were enriched in intracellular protein synthesis and transportation. CONCLUSION: The four gene pair signature can predict the prognosis of patients with stage I LUAD. Our study provides a reference for patients with postoperative adjuvant therapy.

Design, synthesis and biological assessment of N-adamantyl, substituted adamantyl and noradamantyl phthalimidines for nitrite, TNF-α and angiogenesis inhibitory activities.

A library of 15 novel and heretofore uncharacterized adamantyl and noradamantyl phthalimidines was synthesized and evaluated for neuroprotective and anti-angiogenic properties. Phthalimidine treatment in LPS-challenged cells effected reductions in levels of secreted TNF-α and nitrite relative to basal amounts. The primary SAR suggests nitration of adamantyl phthalimidines has marginal effect on TNF-α activity but promotes anti-nitrite activity; thioamide congeners retain anti-nitrite activity but are less effective reducing TNF-α. Site-specific nitration and thioamidation provided phthalimidine 24, effecting an 88.5% drop in nitrite concurrent with only a 4% drop in TNF-α. Notable anti-angiogenesis activity was observed for 20, 21 and 22.

Pomalidomide mitigates neuronal loss, neuroinflammation, and behavioral impairments induced by traumatic brain injury in rat.

BACKGROUND: Traumatic brain injury (TBI) is a global health concern that typically causes emotional disturbances and cognitive dysfunction. Secondary pathologies following TBI may be associated with chronic neurodegenerative disorders and an enhanced likelihood of developing dementia-like disease in later life. There are currently no approved drugs for mitigating the acute or chronic effects of TBI. METHODS: The effects of the drug pomalidomide (Pom), an FDA-approved immunomodulatory agent, were evaluated in a rat model of moderate to severe TBI induced by controlled cortical impact. Post-TBI intravenous administration of Pom (0.5 mg/kg at 5 or 7 h and 0.1 mg/kg at 5 h) was evaluated on functional and histological measures that included motor function, fine more coordination, somatosensory function, lesion volume, cortical neurodegeneration, neuronal apoptosis, and the induction of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6). RESULTS: Pom 0.5 mg/kg administration at 5 h, but not at 7 h post-TBI, significantly mitigated the TBI-induced injury volume and functional impairments, neurodegeneration, neuronal apoptosis, and cytokine mRNA and protein induction. To evaluate underlying mechanisms, the actions of Pom on neuronal survival, microglial activation, and the induction of TNF-α were assessed in mixed cortical cultures following a glutamate challenge. Pom dose-dependently ameliorated glutamate-mediated cytotoxic effects on cell viability and reduced microglial cell activation, significantly attenuating the induction of TNF-α. CONCLUSIONS: Post-injury treatment with a single Pom dose within 5 h significantly reduced functional impairments in a well-characterized animal model of TBI. Pom decreased the injury lesion volume, augmented neuronal survival, and provided anti-inflammatory properties. These findings strongly support the further evaluation and optimization of Pom for potential use in clinical TBI.

In vivo screening and discovery of novel candidate thalidomide analogs in the zebrafish embryo and chicken embryo model systems.

Thalidomide, a drug known for its teratogenic side-effects, is used successfully to treat a variety of clinical conditions including leprosy and multiple myeloma. Intense efforts are underway to synthesize and identify safer, clinically relevant analogs. Here, we conduct a preliminary in vivo screen of a library of new thalidomide analogs to determine which agents demonstrate activity, and describe a cohort of compounds with anti-angiogenic properties, anti-inflammatory properties and some compounds which exhibited both. The combination of the in vivo zebrafish and chicken embryo model systems allows for the accelerated discovery of new, potential therapies for cancerous and inflammatory conditions.

Transiently lowering tumor necrosis factor-α synthesis ameliorates neuronal cell loss and cognitive impairments induced by minimal traumatic brain injury in mice.

BACKGROUND: The treatment of traumatic brain injury (TBI) represents an unmet medical need, as no effective pharmacological treatment currently exists. The development of such a treatment requires a fundamental understanding of the pathophysiological mechanisms that underpin the sequelae resulting from TBI, particularly the ensuing neuronal cell death and cognitive impairments. Tumor necrosis factor-alpha (TNF-α) is a cytokine that is a master regulator of systemic and neuroinflammatory processes. TNF-α levels are reported to become rapidly elevated post TBI and, potentially, can lead to secondary neuronal damage. METHODS: To elucidate the role of TNF-α in TBI, particularly as a drug target, the present study evaluated (i) time-dependent TNF-α levels and (ii) markers of apoptosis and gliosis within the brain and related these to behavioral measures of 'well being' and cognition in a mouse closed head 50 g weight drop mild TBI (mTBI) model in the presence and absence of post-treatment with an experimental TNF-α synthesis inhibitor, 3,6'-dithiothalidomide. RESULTS: mTBI elevated brain TNF-α levels, which peaked at 12 h post injury and returned to baseline by 18 h. This was accompanied by a neuronal loss and an increase in astrocyte number (evaluated by neuronal nuclei (NeuN) and glial fibrillary acidic protein (GFAP) immunostaining), as well as an elevation in the apoptotic death marker BH3-interacting domain death agonist (BID) at 72 h. Selective impairments in measures of cognition, evaluated by novel object recognition and passive avoidance paradigms - without changes in well being, were evident at 7 days after injury. A single systemic treatment with the TNF-α synthesis inhibitor 3,6'-dithiothalidomide 1 h post injury prevented the mTBI-induced TNF-α elevation and fully ameliorated the neuronal loss (NeuN), elevations in astrocyte number (GFAP) and BID, and cognitive impairments. Cognitive impairments evident at 7 days after injury were prevented by treatment as late as 12 h post mTBI but were not reversed when treatment was delayed until 18 h. CONCLUSIONS: These results implicate that TNF-α in mTBI induced secondary brain damage and indicate that pharmacologically limiting the generation of TNF-α post mTBI may mitigate such damage, defining a time-dependent window of up to 12 h to achieve this reversal.

Association between XRCC1 polymorphisms and glioma risk among Chinese population.

The pathogenesis of glioma remains largely unknown now. It has been suggested that the X-ray cross-complementing group 1 (XRCC1) gene may influence the capacity to repair DNA damage leading to an increased gliomas susceptibility. This study aimed to evaluate the relationship between XRCC1 polymorphisms and glioma risk. Genotypes were assessed in 368 Chinese glioma patients and 346 healthy controls. XRCC1 Arg194Trp (rs1799782), Arg280His (rs25489) and Arg399Gln (rs25487) and three additional polymorphisms were directly sequenced. The frequency of Arg280His A allele was significant lower in glioma group than in healthy controls [9.6 vs 16%, OR=0.60 (0.46-0.80), P<0.001]; the frequencies of GA or AA genotypes were different in two groups (16.6 vs 22.8%, 1.3 vs 4.7%). The frequency of Arg399Gln A allele was significant higher in glioma group than in healthy controls [38.7 vs 30.1%, OR=1.29 (1.11-1.49), P=0.001]; the frequencies of GA or AA genotypes were different in two groups (45.4 vs 38.2%, 16 vs 10.9%). This study demonstrates that the rs25489 (Arg280His) and Arg399Gln (rs25487) polymorphisms in XRCC1 gene might influence the risk of developing glioma in Chinese population.

Use of a transanal drainage tube for prevention of anastomotic leakage and bleeding after anterior resection for rectal cancer.

BACKGROUND: The aim of the present study was to investigate the usefulness of the transanal drainage tube for prevention of anastomotic leakage and bleeding after anterior resection for rectal cancer. METHODS: Between January 2007 and May 2011 a nonrandomized prospective study of patients undergoing anterior resection for rectal cancer was done. The patients were divided into the transanal drainage tube (TDT) and non-transanal drainage tube (NTDT) groups according to whether the transanal drainage tube was used in the operation. Clinical characteristics and postoperative complications were compared between the TDT and NTDT groups. RESULTS: The study included 81 patients in the TDT group and 77 patients in the NTDT group. In the TDT group, anastomotic leakage occurred in 2 patients and no anastomotic bleeding occurred. In the NTDT group, anastomotic leakage occurred in 7 patients and anastomotic bleeding occurred in 2 patients. The TDT group had significantly fewer anastomotic complications compared with the NTDT group (2.5 vs 11.7 %; P = 0.029). Furthermore, the TDT group showed an obvious reduction in the rate of anastomotic leakage and anastomotic bleeding compared with the NTDT group (2.5 vs 7.8 % and 0.0 vs 2.6 %), but because the number of cases is relatively small, the difference did not reach statistical significance (P = 0.160 and P = 0.236). CONCLUSIONS: The use of a transanal drainage tube in anterior resection for rectal cancer may be a simple, safe, and effective means of preventing or reducing the occurrence of anastomotic leakage and bleeding. A larger-scale single or multi-center prospective randomized study or a meta-analysis including similar studies is necessary for further elucidation of this issue.

Tumor necrosis factor-α synthesis inhibitor 3,6'-dithiothalidomide attenuates markers of inflammation, Alzheimer pathology and behavioral deficits in animal models of neuroinflammation and Alzheimer's disease.

BACKGROUND: Neuroinflammation is associated with virtually all major neurodegenerative disorders, including Alzheimer's disease (AD). Although it remains unclear whether neuroinflammation is the driving force behind these disorders, compelling evidence implicates its role in exacerbating disease progression, with a key player being the potent proinflammatory cytokine TNF-α. Elevated TNF-α levels are commonly detected in the clinic and animal models of AD. METHODS: The potential benefits of a novel TNF-α-lowering agent, 3,6'-dithiothalidomide, were investigated in cellular and rodent models of neuroinflammation with a specific focus on AD. These included central and systemic inflammation induced by lipopolysaccharide (LPS) and Aß(1-42) challenge, and biochemical and behavioral assessment of 3xTg-AD mice following chronic 3,6'-dithiothaliodmide. RESULTS: 3,6'-Dithiothaliodmide lowered TNF-α, nitrite (an indicator of oxidative damage) and secreted amyloid precursor protein (sAPP) levels in LPS-activated macrophage-like cells (RAW 264.7 cells). This translated into reduced central and systemic TNF-α production in acute LPS-challenged rats, and to a reduction of neuroinflammatory markers and restoration of neuronal plasticity following chronic central challenge of LPS. In mice centrally challenged with A(ß1-42) peptide, prior systemic 3,6'-dithiothalidomide suppressed Aß-induced memory dysfunction, microglial activation and neuronal degeneration. Chronic 3,6'-dithiothalidomide administration to an elderly symptomatic cohort of 3xTg-AD mice reduced multiple hallmark features of AD, including phosphorylated tau protein, APP, Aß peptide and Aß-plaque number along with deficits in memory function to levels present in younger adult cognitively unimpaired 3xTg-AD mice. Levels of the synaptic proteins, SNAP25 and synaptophysin, were found to be elevated in older symptomatic drug-treated 3xTg-AD mice compared to vehicle-treated ones, indicative of a preservation of synaptic function during drug treatment. CONCLUSIONS: Our data suggest a strong beneficial effect of 3,6'-dithiothalidomide in the setting of neuroinflammation and AD, supporting a role for neuroinflammation and TNF-α in disease progression and their targeting as a means of clinical management.

TNF-α protein synthesis inhibitor restores neuronal function and reverses cognitive deficits induced by chronic neuroinflammation.

BACKGROUND: Chronic neuroinflammation is a hallmark of several neurological disorders associated with cognitive loss. Activated microglia and secreted factors such as tumor necrosis factor (TNF)-α are key mediators of neuroinflammation and may contribute to neuronal dysfunction. Our study was aimed to evaluate the therapeutic potential of a novel analog of thalidomide, 3,6'-dithiothalidomide (DT), an agent with anti-TNF-α activity, in a model of chronic neuroinflammation. METHODS: Lipopolysaccharide or artificial cerebrospinal fluid was infused into the fourth ventricle of three-month-old rats for 28 days. Starting on day 29, animals received daily intraperitoneal injections of DT (56 mg/kg/day) or vehicle for 14 days. Thereafter, cognitive function was assessed by novel object recognition, novel place recognition and Morris water maze, and animals were euthanized 25 min following water maze probe test evaluation. RESULTS: Chronic LPS-infusion was characterized by increased gene expression of the proinflammatory cytokines TNF-α and IL-1ß in the hippocampus. Treatment with DT normalized TNF-α levels back to control levels but not IL-1ß. Treatment with DT attenuated the expression of TLR2, TLR4, IRAK1 and Hmgb1, all genes involved in the TLR-mediated signaling pathway associated with classical microglia activation. However DT did not impact the numbers of MHC Class II immunoreactive cells. Chronic neuroinflammation impaired novel place recognition, spatial learning and memory function; but it did not impact novel object recognition. Importantly, treatment with DT restored cognitive function in LPS-infused animals and normalized the fraction of hippocampal neurons expressing the plasticity-related immediate-early gene Arc. CONCLUSION: Our data demonstrate that the TNF-α synthesis inhibitor DT can significantly reverse hippocampus-dependent cognitive deficits induced by chronic neuroinflammation. These results suggest that TNF-α is a critical mediator of chronic neuroinflammation-induced neuronal dysfunction and cognitive impairment and targeting its synthesis could provide an effective therapeutic approach to several human neurodegenerative diseases.

Tumor necrosis factor-α synthesis inhibitor, 3,6'-dithiothalidomide, reverses behavioral impairments induced by minimal traumatic brain injury in mice.

Mild traumatic brain injury (mTBI) patients do not show clear structural brain defects and, in general, do not require hospitalization, but frequently suffer from long-lasting cognitive, behavioral and emotional difficulties. Although there is no current effective treatment or cure for mTBI, tumor necrosis factor-alpha (TNF-α), a cytokine fundamental in the systemic inflammatory process, represents a potential drug target. TNF-α levels increase after mTBI and may induce or exacerbate secondary damage to brain tissue. The present study evaluated the efficacy of the experimental TNF-α synthesis inhibitor, 3,6'-dithiothalidomide, on recovery of mice from mTBI in a closed head weight-drop model that induces an acute elevation in brain TNF-α and an impairment in cognitive performance, as assessed by the Y-maze, by novel object recognition and by passive avoidance paradigms at 72 h and 7 days after injury. These impairments were fully ameliorated in mice that received a one time administration of 3,6'-dithiothalidomide at either a low (28 mg/kg) or high (56 mg/kg) dose provided either 1 h prior to injury, or at 1 or 12 h post-injury. Together, these results implicate TNF-α as a drug target for mTBI and suggests that 3,6'-dithiothalidomide may act as a neuroprotective drug to minimize impairment.

Thalidomide Analogues Suppress Lipopolysaccharide-Induced Synthesis of TNF-α and Nitrite, an Intermediate of Nitric Oxide, in a Cellular Model of Inflammation.

An unregulated neuroinflammation accompanies numerous chronic and acute neurodegenerative disorders and it is postulated that such a neuroinflammatory component likely exacerbates disease progression. A key player in brain inflammation is the microglial cell; a vital soluble factor synthesized by activated microglial cells is the key cytokine, tumor necrosis factor-alpha (TNF-α). Additionally, microglial cells release IL-1α/ß, reactive oxygen species (ROS), such as superoxide (O(2) (-)) and reactive nitrogen species (RNS) like nitric oxide (NO). Nitric oxide reactive oxygen species can undergo various forms of interactions in cells whereby the synthesis of RNS / ROS intermediates are generated that can damage cell membranes. The presence of oxidative damaged cells is implicated with the abnormal cellular activity in brain or in the spinal cord, and is a classical feature of neurodegenerative disorders. To aid characterize this process, a quantitative analysis of nitrite generation was undertaken on agents developed to lower TNF-α levels in cell culture. Nitrite is a stable end product of nitric oxide metabolism and, thereby, acts as a surrogate measure of the highly unstable nitric oxide. Utilizing a RAW 264.7 cellular model of lipopolysaccharide-induced inflammation that induces high levels of TNF-α protein accompanied by a robust generation of nitrite, the properties of a series of thalidomide-based TNF-α synthesis inhibitors were evaluated to reduce the levels of both. Specific analogues of thalidomide effectively suppressed the generation of both TNF-α and nitrite at well-tolerated doses.