Patent Abstract:
geriatric depression is treated with l - carnitine or an alkanoyl l - carnitine , desirably acetyl l - carnitine thereby avoiding unwanted side - effects exhibited by conventional antidepressant agents .

Detailed Description:
in the context of the invention described herein , it has been found , in an entirely unexpected way , that the use of a therapeutically effective amount of l - carnitine or of an alkanoyl l - carnitine , in which the linear or branched alkanoyl has 2 - 8 carbon atoms , or one of its pharmacologically acceptable salts , is beneficial to depressed subjects , particularly in geriatric patients , without a disturbing side - effect profile exhibited by traditional antidepressants and improving the quality of life itself in the subjects treated , whether human subjects or animals . where r is hydrogen or an alkanoyl group with 2 to 8 carbon atoms , and x − represents the anion of a pharmaceutically acceptable salt . the invention described herein includes both the administration of l - carnitine or an alkanoyl l - carnitine or one of its pharmacologically acceptable salts of formula ( i ) in the treatment of depression , and pharmaceutical compositions , which can be administered orally , parenterally or nasally , including controlled - release forms . preferably , the alkanoyl l - carnitine is selected from the group consisting of acetyl l - carnitine ( hereinafter abbreviated to alc or alcar ), propionyl l - carnitine ( hereinafter abbreviated to plc ), butyryl l - carnitine , valeryl l - carnitine and isovaleryl l - carnitine , or one of their pharmacologically acceptable salts . the ones preferred are acetyl l - carnitine , propionyl l - carnitine and butyryl l - carnitine . the most preferred is acetyl l - carnitine . what is meant by a pharmacologically acceptable salt of l - carnitine or of an alkanoyl l - carnitine is any salt of the latter with an acid that does not give rise to toxic or side effects . these acids are well known to pharmacologists and to experts in pharmaceutical technology . examples of pharmacologically acceptable salts of l - carnitine or of the alkanoyl l - carnitines , though not exclusively these , are chloride ; bromide ; iodide ; aspartate ; acid aspartate ; citrate ; acid citrate ; tartrate ; acid tartrate ; phosphate ; acid phosphate ; fumarate ; acid fumarate ; glycerophosphate ; glucose phosphate ; lactate ; maleate ; acid maleate ; mucate ; orotate , oxalate ; acid oxalate ; sulphate ; acid sulphate ; trichloroacetate ; trifluoroacetate ; methane sulphonate ; pamoate and acid pamoate . as used herein , a geriatric subject is an individual 65 years of age or older . see the merck manual , 15 th edition ( 1987 ) p . 2389 . one preferred form of daily dosing of l - carnitine or alkanoyl l - carnitine for clinical use is a composition comprising an amount of l - carnitine or an alkanoyl l - carnitine , preferably acetyl or propionyl l - carnitine , equivalent to 0 . 1 to 3 g , and preferably 0 . 5 to 3 g per day . phosphorus magnetic resonance spectroscopic imaging ( 31 p mrsi ) analysis of two depressed elderly subjects treated with alcar for 12 weeks are compared with those of six normal non - demented , non - depressed subjects . a twelve - week , open , clinical , 31 p mrsi study design was used to examine the possible effects of alcar on brain metabolism and depressive symptomatology in non - demented geriatric major depressive disorder ( ndg - mdd ). two depressed , non - demented [ folstein mini - mental state exam ( mmse )& gt ; 24 )] male subjects , 70 and 80 years old , were compared with six age , social - economic status , and medically matched non - demented controls ( all male , mean age of 73 . 6 ± 3 . 6 years , range 69 . 7 - 78 . 2 years ). the two elderly depressed subjects completed baseline structural clinical interview of dsm - iv ( scid ) i / p version 2 . 0 , hdrs ( 17 item ), mmse , uku side effect rating scale ( uku ), and cumulative illness rating scale ( cirs ) to assess medical burden , baseline physical , ecg , and , laboratory tests for hematology , urine analysis , immunopathology , and blood chemistry . follow - up visits for the depressed subjects were done every other week for 12 weeks . efficacy ( psychiatric evaluation ) was assessed by changes in the hdrs which was performed at baseline and every other week for 12 weeks along with secondary measures ( mmse ; cirs ; and uku ), whereas the cirs was performed at baseline , 6 , and 12 weeks . physical examinations and ekgs were performed at baseline , 6 , and 12 weeks . the baseline mr evaluation was scheduled and completed prior to the administration of alcar . follow - up mr evaluations were at 6 and 12 weeks . acetyl - l - carnitine was administered in the form of oral tablets containing 590 mg of acetyl - l - carnitine hydrochloride ( 500 mg acetyl - l - carnitine ). the dosage regimen was fixed at three grams of acetyl - l - carnitine given two tablets three times a day for 12 weeks . [ 0021 ] 31 p mrsi acquisition — a custom built , doubly tuned transmit / receive volume head coil was used to acquire the 1 h mri and 2d 31 p mrsi data on a ge signa 1 . 5 t whole body mr imager . first , sets of axial and sagittal scout mr images were collected . the 30 mm thick mrsi slice was positioned parallel with the anterior commisure - posterior commisure line to include the right and left prefrontal , basal ganglia , superior temporal , inferior parietal , occipital , and centrum semiovale regions . a self - refocused spin echo pulse sequence with an effective flip range of 60 ° and an echo time of 2 . 5 ms , was used to acquire the 31 p mrsi ( 360 mm field of view , 30 mm slice thickness , 8 × 8 phase encoding steps [ 45 × 45 × 30 mm 3 nominal voxel dimensions ], 2 s tr , 1024 data points , 4 . 0 khz spectral bandwidth and 16 nex ). mrsi post - processing and quantification — to optimize the right and left voxel positions for the six regions , the 8 × 8 31 p grid was shifted with respect to the anatomical mri and a mild spatial apodization ( i . e ., fermi window with 90 % diameter and 5 % transition width ) was applied prior to the inverse fourier transform . the remaining processing steps were 100 % automated . a 5 hz exponential apodization was applied and the pme , phosphodiester ( pde ), pcr , α -, γ -, and β - atp , and inorganic orthophosphate ( pi ), were modeled in the time domain with exponentially damped sinusoids and by omitting the first 2 . 75 ms of the free induction decay ( fid ) using the marquardt - levenberg algorithm . this approach ensured that the pme and pde resonances primarily reflected the freely mobile , short correlation time ( s − τ c ), water soluble pme ( s − τ c ) and pde ( s − τ c ) metabolites without the influence of relatively broad underlying signals within the pme and pde spectral region . the pme ( s − τ c ) ( i . e ., phosphoethanolamine , phosphocholine , and inositol - 1 - phosphate ) are predominantly building blocks of phospholipids and therefore , the relative concentrations of these metabolites are a measure of the active synthesis of membranes ; the pde ( s − τ c ) ( i . e ., glycerophosphocholine and glycerophosphoethanolamine ) are major products of membrane degradation . to obtain intermediate correlation time ( i − τ c ) components within the pme and pde spectral region , the fids were modeled a second time but with omitting the first 0 . 75 ms of the fid and then taking the difference between the pme and pde amplitudes of the two modeled results . pme ( i − τ c ) moieties include less mobile molecules such as phosphorylated proteins and pmes that are tightly coupled ( in terms of mrs ) to macromolecules [ i . e ., pmes inserting into membrane phospholipids . pde ( i − τ c ) moieties include less mobile pdes that are part of small membrane phospholipid structures such as micelles , synaptic vesicles , and transport / secretory vesicles and pde moieties coupled to larger molecular structures ( i . e ., pdes inserting into membrane phospholipid structures . the right / left side effect was eliminated by averaging the signal from the two voxels , prior to fitting ( which included correcting for phase and resonance frequency ). additionally , metabolite levels are expressed as a mole % relative to the total 31 p signal . the statistical analysis was done using the statview ( sas institute , inc .) software package . the pearson t correlation test used to correlate between variables . the two elderly depressed subjects were diagnosed with mdd according to dsm - iv criteria . no previous antidepressant medications were taken by the subjects in the three months prior to the study . subject # 1 has baseline , 6 and 12 week hdrs scores of 15 , 1 and 0 and subject # 2 had scores of 20 , 17 , and 3 , respectively . thus both depressed subjects were clinically improved at endpoint , fulfilling criteria for remission ( hdrs & lt ; 8 ). medical conditions diagnosed in the depressed subjects included s / p knee arthroscopy , s / p cervical disk removal , hearing loss and benign prostatic hypertrophy in subject # 1 and benign prostatic hypertrophy in subject # 2 . no clinically significant abnormalities were found in the laboratory exams and ekg of either depressed subject . baseline , 6 , and 12 weeks cirs were 7 , 6 , and 5 for subject # 1 ; and 4 , 4 , and 2 for subject # 2 , respectively . the change reflects the improvement of depressive symptomatology . side effects from alcar treatment were mild and included dry mouth in subject # 1 and a slight increase in perspiration in subject # 2 . [ 0025 ] fig1 shows the correlation of pme ( s − τ c ) ( r = 0 . 86 , p = 0 . 069 and pcr ( r = 0 . 97 , p = 0 . 002 ) levels from the prefrontal region with hdrs scores for both depressed subjects . fig2 illustrates the prefrontal and basal ganglia pcr and pme ( s − τ c ) levels at baseline , 6 and 12 weeks for the two depressed subjects and the mean pcr and pme ( s − τ c ) levels for the six normal controls . unfortunately , the 6 week 31 p mrsi session for subject # 1 produced poor quality , unacceptable data and this time point is missing from the graphs . baseline prefrontal pme ( s − τ c ) levels in the depressed subjects were 1 . 5 to 2 . 0 sd higher than the mean of the controls and this increase was normalized with alcar treatment . both depressed subjects had prefrontal pcr levels one sd higher than the mean of controls and alcar treatment further increased pcr levels by 27 % and 31 %, respectively . similar changes in pme ( s − τ c ) and pcr levels also were observed in the basal ganglia region ( fig2 ), but these metabolite levels did not correlate with hdrs scores . although the most marked changes occur in the prefrontal region , z - score plots of the significant pme ( s − τ c ) and pcr changes between depressed subjects and controls illustrates the other brain regions also undergo changes with alcar treatment . fig3 demonstrates that compared with normal subjects , the two untreated depressed subjects at baseline had increased levels of pme ( s − τ c ) in the prefrontal region ( p = 0 . 006 ). after 12 weeks of alcar treatment , the pme ( s − τ c ) are normalized in the prefrontal regions but elevated in the superior temporal regions ( p = 0 . 05 . in addition , pcr levels are elevated in the prefrontal ( p = 0 . 001 ), basal ganglia ( p = 0 . 022 ), and occipital ( p = 0 . 027 regions after 12 weeks of alcar treatment . there were no significant changes in the other metabolite levels . while not wishing to be bound by any particular theory , the above findings suggest that beneficial clinical effects of acetyl - l - carnitine appear to be associated with changes in brain prefrontal pme ( s − τ c ) and pcr levels . in the prefrontal region , the depressed subjects compared with controls after 12 weeks of alcar treatment show normalization of pme ( s − τ c ) and elevation of pcr levels . the pme ( s − τ c ) resonance is predominantly composed of phosphocholine , phosphoethanolamine and inositol - 1 - phosphate which are precursors in membrane phospholipid metabolism . the increased pme ( s − τ c ) in depression , as also observed by others is not fully understood and will require further study . alcar treatment seems to restore pme ( s − τ c ) levels to normal and there was a trend for the decreasing pme levels to correlate with clinical improvement . in the prefrontal region , twelve weeks of alcar treatment also elevated pcr , a high - energy phosphate metabolite which is an immediate precursor of atp . compared with the control group , similar findings were observed for basal ganglia pme ( s − τ c ) and pcr levels , but the metabolite levels did not correlate with hdrs scores . this may be due to the small number of depressed patients analyzed . other brain regions may be affected by depression and these changes may be altered by alcar treatment ( fig3 ). while the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment , it is to be understood that the invention is not to be limited to the disclosed embodiment , but on the contrary , is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims . 1 . reynolds c f , frank e , perel j , mazumdar s , kupfer d j . maintenance therapies for late - life recurrent major depression : research and review circa 1995 . int psychogeriatr 1995 ; 7 : 27 - 40 . 2 . hsu j h , shen w w . male sexual side effects associated with antidepressants : a descriptive clinical study of 32 patients . int j psychiatry med 1995 ; 25 : 191 - 201 . 3 . nelva a , guy c , tardy - poncet b , beyens m n , ratrema m , benedetti c , ollagnier m . 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