Deciphering psilocybin: Cytotoxicity, anti-inflammatory effects, and mechanistic insights

A decade of clinical research has indicated psilocybin's effectiveness in treating various neuropsychiatric disorders, such as depression and substance abuse. The correlation between increased pro-inflammatory cytokines and the severity of neuropsychiatric symptoms, along with the known anti-inflammatory potential of some psychedelics, suggests an immunomodulatory role for psilocybin. This study aims to understand the mechanism of action of psilocybin by investigating the cytotoxic and immunomodulatory effects of psilocybin and psilocin on both resting and LPS-activated RAW 264.7 murine macrophages. The study evaluated the cytotoxicity of psilocybin and psilocin using an LDH assay across various doses and assessed their impact on cytokine production in RAW 264.7 cells, measuring cytokine expression via ELISA. Different doses, including those above and below the LC50, were used in both pre-treatment and post-treatment approaches. The LDH assay revealed that psilocybin is almost twice as cytotoxic as psilocin, with an LC50 of 12 ng/ml and 28 ng/ml, respectively. In resting macrophages, both psilocybin and psilocin triggered significant release of TNF- α after 4 h, with the lowest doses inducing higher levels of the cytokine than the highest doses. IL-10 expression in resting cells was only triggered by the highest dose of psilocin in the 4-hour incubation group. In LPS-stimulated cells, psilocin reduced TNF- α levels more than psilocybin in pre-treatment and post-treatment, with no significant effects on IL-10 in pre-treatment. Psilocin, but not psilocybin, induced a significant increase of IL-10 in post-treatment, leading to the conclusion that psilocin, but not psilocybin, exerts anti-inflammatory effects on classically activated macrophages.

Combined modality treatment for organ preservation in patients with invasive bladder cancer

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Purpose: To evaluate long term results of chemoradiation and organ preservation in invasive T2-T4a bladder carcinoma in a single institution with prolonged follow up. Methods: Sixty one patients with clinical stage II and III (T3N0) muscle invasive bladder carcinoma were treated between February 1991 and December 2007. Forty four received sequential treatment (chemo followed by radiation) and seventeen concurrent treatments. Chemotherapy was platinum based in all patients, fifth teen with Carboplatin. All underwent maximal citoreduction with TUR .First 20 patients received pelvic radiation (1991–1993),while the other 41 three-dimensional radiotherapy (median dose 60 Gy). Male/female 55/6: median age 64 (range 46–80); transitional type 58 and mixed-epidermoid 6. Grade II: 3, grade III: 48 and grade IV: 10. Clinical stage II:50 and III:11. Mean follow up 63 months. Results: The 5 year overall survival rate was 57%. Forty patients remained NED, with eight deaths due to second primary or cardiovascular disease. Twenty pts were treated more than 5 years ago, 16(80%) are alive, 14 NED,2 pts relapsed after 5 years. Of all predictive factors analyzed only clinical stage reached statistical significance for relapse (p=0.0029), and borderline significance for overall survival (p=0.064). Toxicity: Grade 3–4: 7%, with 3% of febrile neutropenia. No patient required cystectomy because of bladder morbidity. Conclusions: Trimodality treatment in selected patients offers rates of event free survival and overall survival similar to those reported for surgery with acceptable toxicity and no treatment related cystectomy. Relapse after 5 year is very uncommon. In this small group of patient results were similar with concurrent and sequential treatment. At present we treat our patients with concurrent chemoradiation with tridimensional technique.

No significant financial relationships to disclose.

Surgical salvage of pelvic recurrences from colorectal tumors

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Background: The morbidity of pelvic recurrences from colorectal tumors (PRCT) represents a challenge for the oncology multidisciplinary team. Surgical treatment is the best option for palliation and in several series it offers long term local control in 30% of the cases. Objective: To perform a retrospective analysis of patients (pts) surgically resected for PRCT in terms of: time to progression after surgical salvage (TP) and specific suvival (SS). Correlatives studies were performed with clinic and pathologic factors, surgical procedures (SP), and postoperative complications in terms of TP and SS. Methods: 64 pts treated (June 1994 - February 2005) were identified (women: 30), median age 63 years, site of the primary: rectum 48, sigmoid 16; Median number of resected nodes: 8 (r: 2 - 20) in pts with negative nodes and 15 (r: 6 - 42) in pts with positive nodes; primary treatment: surgery (S): 22 pts, S + chemotherapy (CT): 18, S + radiotherapy (RT): 4, S + CT/RT: 17, CT + S: 2 pts, QT/RT + CX: 1; in 7/64 a Miles procedure was performed as primary therapy, median disease free interval: 15 months; site of initial recurrence: locoregional 58 (90%), locoregional + systemic 10%. Pain and bleeding were the most frecuent symptoms. Results: The strategy in PRCT was: S: 29 pts, S + RT: 15, S + CT/RT: 9, CT/RT + S: 7, S + CT: 2, CT + S: 1, RT + S:1; IORT: 18/64; external beam RT: 17/64, 6 pts required Miles; type of resection: R0: 50/64 (78%), R1: 8/64 (12%), R2: 3/64 (5%) and 3 (5%) unknown. Median duration of surgery: 4 hours, abscesses and fistulas were the complications most frequently observed. Median time to progression (TP): 12 months, site of recurrence (56/64 pts) post salvage surgery: pelvic: 22 pts, extrapelvic: 6 pts, combined: 10 and unknown 18. Eleven pts are free of disease. In 16 pts more than one surgical salvage was perfomed. The specific survival was 21 months (IC 95% 37 - 61 m). Conclusions: In this serie surgical salvage of PRCT showed one year of local control disease, even in pts with R2 and with moderate morbidity. The surgical decision must be individualized and in the context of a trained surgical team.

No significant financial relationships to disclose.

Surgical and non-surgical treatment of pulmonary metastases of soft tissue sarcomas

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Background: Several reports have shown a prolonged survival after surgery for lung metastases from soft tissue sarcomas (STS). This finding is in contrast with the results from chemotherapy. We performed a retrospective analysis to determine the impact of surgical and non surgical treatment in terms of time to progression (TTP) and disease specific survival (DSS). Methods: A review of 144 patients (pts) with STS treated at a single institution (december 1994-february 2005) was performed. Median age: 45 years old, female 53%. Extremity was the primary site in 54 pts and leiomyosarcoma was the most common histologic type (24%). In 42 pts pulmonary metastases were synchronous. The median disease free interval (DFI) was 11 months. Surgical treatment on the lung lesions was performed in 48 pts (group A), while 96 received medical treatment (group B). Results: Surgery was R0 in 90% of group A pts with only 4 lobectomies and 36 metastasectomies. Nine pts (19%) in this group received neo or adyuvant chemotherapy. The median TTP was 11 months (2–107) and 21 pts (44%) relapse in the lung (8 lung + other site). At the time of this analysis 13 pts (27%) are NED, with a DSS of 24 months for the surgical group. 28% remain alive at 5 years. In a univariate analysis only the number of lung metastases (1 vs 2 or more) was significant for DSS (p=0.05). Group B was treated primarily with chemotherapy being doxorubicin the most common drug used (89%). The RR was 23% with a median TTP of 3 months and a DSS of 12 months (1–98). Conclusions: The present results are similar with previous reports in terms of overall survival. Paliative chemotherapy showed modest activity and surgical treatment remains the only curative treatment modality for pts with lung metastases from STS.

No significant financial relationships to disclose.

Neural network modelling of dynamic cerebral autoregulation: assessment and comparison with established methods

A time lagged recurrent neural network (TLRN) was implemented to model the dynamic relationship between arterial blood pressure (ABP) and cerebral blood flow velocity (CBFV) and its performance was compared to classical linear model such as transfer function analysis, Aaslid's dynamic autoregulation model, and the Wiener-Laguerre moving average filter. A simple linear regression was also tested as a naive estimator. In 16 normal subjects, CBFV was continuously recorded with Doppler ultrasound and ABP with the Finapres device during six repeated thigh cuff manoeuvres. Using mean beat-to-beat values of ABP as input and CBFV as output, the performance of each method was assessed by the model's predicted velocity correlation coefficient and normalized mean square error (MSE). Cross-validation was performed using three thigh cuff manoeuvres for the training data set and the other three for the validation set. The four methods studied performed significantly better than the zero-order naive estimator. The TLRN performed better than transfer function analysis, but was not significantly different from the time-domain techniques, despite showing the minimum predictive MSE. CBFV step responses could be extracted from the TLRN showing the presence of non-linear behaviour both in terms of amplitude and directionality.

Chronic hypoxia up-regulates fibroblast growth factor ligands in the perinatal brain and induces fibroblast growth factor-responsive radial glial cells in the sub-ependymal zone

A number of signaling molecules have been implicated in the acute response to hypoxia/ischemia in the adult brain. In contrast, the reaction to chronic hypoxemia is largely unexplored. We used a protocol of chronic hypoxia in rat pups during the first three postnatal weeks, encompassing the period of cellular plasticity in the cerebral cortex. We find that the levels of fibroblast growth factor 1 (FGF1) and FGF2, two members of the FGF family, increase after 2 weeks of chronic hypoxia. In contrast, members of the neurotrophin family are unaffected. FGF2 is normally expressed in the nucleus of mature, glial fibrillary acidic protein (GFAP)-containing astrocytes. Under hypoxia, most FGF2-containing cells do not express detectable levels of GFAP, suggesting that chronic low O(2) induces their transformation into more immature glial phenotypes. Remarkably, hypoxia promotes the appearance of radial glia throughout the sub-ventricular and ependymal zones. Most of these cells express vimentin and brain lipid binding protein. A subset of these radial glial cells expresses FGF receptor 1, and are in close contact with FGF2-positive cells in the sub-ventricular zone. Thus, FGF receptor signaling in radial glia may foster cell genesis after chronic hypoxic damage. From the results of this study we suggest that after the chronic exposure to low levels of oxygen during development, the expression of radial glia increases in the forebrain periventricular region. We envision that astroglia, which are the direct descendants of radial glia, are reverting back to immature glial cells. Alternatively, hypoxia hinders the normal maturation of radial glia into GFAP-expressing astrocytes. Interestingly, hypoxia increases the levels of expression of FGF2, a factor that is essential for neuronal development. Furthermore, chronic hypoxia up-regulated FGF2's major receptor in the periventricular region. Because radial glia have been suggested to play a key role in neurogenesis and cell migration, our data suggests that hypoxia-induced FGF signaling in radial glia may represent part of a conserved program capable of regenerating neurons in the brain after injury.

Expression of angiogenesis-related molecules in plexiform lesions in severe pulmonary hypertension: evidence for a process of disordered angiogenesis

Pulmonary arteries of patients with severe pulmonary hypertension (SPH) presenting in an idiopathic form (primary PH-PPH) or associated with congenital heart malformations or collagen vascular diseases show plexiform lesions. It is postulated that in lungs with SPH, endothelial cells in plexiform lesions express genes encoding for proteins involved in angiogenesis, in particular, vascular endothelial growth factor (VEGF) and those involved in VEGF receptor-2 (VEGFR-2) signalling. On immunohistochemistry and in situ hybridization, endothelial cells in the plexiform lesions expressed VEGF mRNA and protein and overexpressed the mRNA and protein of VEGFR-2, and the transcription factor subunits HIF-1alpha and HIF-1beta of hypoxia inducible factor, which are responsible for the hypoxia-dependent induction of VEGF. When compared with normal lungs, SPH lungs showed decreased expression of the kinases PI3 kinase and src, which, together with Akt, relay the signal transduction downstream of VEGFR-2. Because markers of angiogenesis are expressed in plexiform lesions in SPH, it is proposed that these lesions may form by a process of disordered angiogenesis.

Application of central composite designs to the preparation of polycaprolactone nanoparticles by solvent displacement

Cyclosporin A (CyA) is a good candidate for incorporation in colloidal carriers such as nanoparticles (NP) that would diminish the adverse effects associated with its use under conventional pharmaceutical dosage forms and improve bioavailability after oral administration. In this study a composite rotational experimental design was used to evaluate the joint influence of five formulation variables: temperature of the aqueous phase, needle gauge, volume of the organic phase, and the amounts of polymer and surfactant on the micromeritic characteristics of the CyA-loaded NP obtained by the method of Fessi et al. The percentage of drug encapsulated in the NP was also evaluated for each formulation, and the yield, which was expressed as the ratio between the experimentally measured quantity of drug in the formulation and the theoretical content, was determined because CyA undergoes surface absorption. Potential variables such as stirring speed (500 rpm), final drug concentration (100 micrograms/mL), or injection rates (GRi = 0.379 mL/s) were maintained constant. The ANOVA corresponding to the experimental design showed that the amounts of polymer and surfactant, and the diameter of the needle used in the preparation of NP, significantly affected the percentage of entrapped drug (I2 = 0.8916). The mean particle size was significantly affected by all the formulation variables tested except for the amount of surfactant dissolved in the external aqueous phase (r2 = 0.9518). Neither the yield (mean value of 99.61%) nor the size distribution parameters (polydispersity and coefficient of variation) presented good correlation coefficients for the equations obtained, although some variables showed statistical significance. A second study was carried out to investigate the effects on the drug-loaded NP characteristics of varying the global injection rates (GRi) for the organic phase into the aqueous medium. The results showed a dramatic decrease in both particle size and drug incorporation in the carrier as the rate of mixing increased. From the results of both the experimental design and the second study, a theoretical model for nanoparticle formation is proposed that considers the most significant variables, and an empirical relationship to predict mean particle size is presented. Thus, particle size can be controlled by the injection rates (GRi), the needle gauge, and the polymer concentration.

The effect of chronic ethanol feeding on ornithine decarboxylase activity and liver regeneration

The effects of ethanol on liver regeneration are poorly understood. Acute and chronic exposure to ethanol have been found to exert opposite effects on the induction of ornithine decarboxylase, the rate-limiting enzyme for polyamine biosynthesis. Polyamines are necessary for DNA synthesis and liver regeneration after chemical or surgical liver injury. Short-term exposure to ethanol, which inhibits ornithine decarboxylase has been shown to inhibit DNA synthesis and liver regeneration, whereas more chronic exposure to ethanol increases ornithine decarboxylase activity and therefore could conceivably stimulate DNA synthesis and regeneration. To explore this later possibility, the effects of chronic ethanol consumption on ornithine decarboxylase activity, DNA synthesis and liver regeneration were studied in rats after sham laparotomy and partial hepatectomy. Chronic ethanol feeding failed to inhibit the induction of ornithine decarboxylase that occurred after partial hepatectomy and yet significantly inhibited posthepatectomy DNA synthesis and restitution of liver mass. These data suggest that the induction of hepatic polyamine biosynthesis is dissociated from DNA synthesis and liver regeneration after chronic consumption of ethanol.

Thyroid hormone actions on a cholinergic neuroblastoma cell line (S-20Y)

Thyroid hormone (T3) has a multiplicity of effects on the developing nervous system. We have investigated T3 action using a cholinergic neuroblastoma cell line (S-20Y) as a model. S-20Y contains a nuclear receptor for T3 with binding properties similar to those of other T3 target tissues. In addition, these cells can carry out 5'-deiodination, which is necessary to produce active thyroid hormone in vivo. The enzyme involved in this process appears to be a type I deiodinase, based on its reaction kinetics and its susceptibility to inhibition by propylthiouracil. S-20Y cells maintained in T3-depleted medium showed decreased choline acetyltransferase (ChAT) activity. ChAT activity was restored to the control level in a dose-dependent manner by T3 repletion. Neither cell density nor viability was influenced by the hypothyroid state. The presence of a T3 receptor and the enzyme activity for T3 production, together with an effect of T3 on ChAT activity, demonstrate that S-20Y cells are a target for T3 action and suggest that these cells represent an excellent model system for studies of T3 effects on nervous tissues.

Fibre-type specificity and effect of thyroid hormone on glucose 6-phosphate dehydrogenase activity in normal and denervated skeletal muscles of the rat

Glucose-6-phosphate dehydrogenase activity increases following denervation of rat skeletal muscle. The specificity of this effect to muscle fibre type was studied. Basal activity of the dehydrogenase was higher in soleus, a muscle composed predominantly of type I fibres, than in extensor digitorum longus, a muscle composed predominantly of type IIa and b fibres. The enzymatic activity of the soleus was also greater than that of the red (RQ) and white (WQ) portions of quadriceps muscle (predominantly type IIa and type IIb fibres, respectively). Following denervation, glucose-6-phosphate dehydrogenase increased in extensor digitorum longus and RQ, but not in WQ or the soleus. Following chronic treatment of rats with 3,3',5-triiodothyronine, which converts type I muscle fibres to type II, the dehydrogenase activity increased in both denervated soleus and extensor digitorum longus. It is concluded that the effect of denervation on glucose-6-phosphate dehydrogenase activity is selective for type IIa (fast oxidative-glycolytic) muscle fibres.

Follicular fluid inhibin activity and steroid levels in ovarian tissue obtained at autopsy from human infants from 18 to 200 days of age

The ovaries of 25 human infants from 18 to 200 days of age were obtained at autopsy, and their follicular fluid was subjected to measurement of inhibin activity, estrogen, progesterone, androstenedione, and testosterone. Significant inhibin activity was present in all samples of follicular fluid (charcoal-treated) (138 +/- 19 U/10 microliter follicular fluid; 10,545 +/- 2758 U/ovary). There was a tendency for greater inhibin activity, follicular volume, and estrogen in infants from 18 to 59 days than in older infants. There was a significant positive correlation between follicular fluid volume, estrogen, and androstenedione, compared with follicular fluid inhibin content per ovary. It is possible that elevated serum follicle-stimulating hormone and luteinizing hormone observed early in life stimulates follicle growth, inhibin, and estrogen production. As a result of elevated inhibin and estrogen, the gonadotropins may be inhibited, which may cause a decline in follicular activity after 4 to 6 months.

Stimulatory effects of follicle-stimulating hormone and luteinizing hormone upon secretion of progesterone and inhibin activity by cultured infant human ovarian granulosa cells

Ovarian tissue obtained from three human infants (60, 120, and 210 days of age) was separated into cell types and cultured. Granulosa cells from two of three subjects were viable and grew in culture. The cells had the potential to secrete low levels of progesterone and responded to luteinizing hormone and follicle-stimulating hormone added in culture with greatly enhanced ability to secrete progesterone. Granulosa cells could also secrete inhibin activity in culture and responded to luteinizing hormone and follicle-stimulating hormone with enhanced inhibin secretion. The granulosa cells also had the potential to secrete estrogen in the presence of testosterone. Serum levels of gonadotropin in the human infant are elevated for a period between 1 and 4 months; yet only follicular growth, not luteinization, occurs. It can be concluded that infant human granulosa cells, like adult human granulosa cells, have the potential of responding in vitro to gonadotropin.

Muscular structural changes following fadenoperation

The authors describe the macroscopic, histological, and ultrastructural findings observed in an experimental animal model of the fadenoperation . Grossly, muscular fibrosis and musculo-scleral adhesions were well established after the second postoperative month. Histologic findings demonstrated the development of a granulomatous, foreign body reaction around the musculo-scleral fixation suture, collagenization of the muscle tissue from the first postoperative month and degenerative phenomena in the muscle fibers. Electron transmission microscopic study showed atrophy and angulation with distortion of the myofibrillar matrix, along with alteration of the Z bands of muscle fibers, mitochondrial alteration, and dilatation of the sarcotubular system. All these experimental findings suggest the relative irreversible effects of the fadenoperation after the early postoperative period and for the first time, demonstrated that this surgical technique alters the muscle structure.

Selective carnitine palmitoyltransferase deficiency in fibroblasts from a patient with muscle CPT deficiency

A 13-year-old boy developed cramps and myoglobinuria following exertion. Mitochondrial preparations from a skeletal muscle biopsy were deficient in carnitine palmitoyltransferase (CPT) activity when assayed by the hydroxamate and kinetic assays. The patient's fibroblasts were also deficient when assayed by the hydroxamate and kinetic assays, but not when tested by the DTNB (5,5'-dithiobis-[nitrobenzoic acid]) method. This disparity probably indicates a specific deficiency in fibroblasts of one of the two carnitine palmitoyltransferases, presumably CPT II.